There are two ways to get guaranteed crispy sweet potato fries. In your oven (yes!) or in a deep fryer. But even deep frying plain sweet potato fries won't get them crispy. You need a tiny bit of the secret ingredient - cornstarch.
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Right here, right now I am going to teach you how to make crispy sweet potato fries. Even though they're not a real french fry. They are french fry substitutes to be eaten when a real french fry can't be found.
Yes, I know. But you loveeeeeeeee sweet potato french fries. You like them wayyyyyyyyyy better than regular french fries. That's because you're an amateur. I on the other hand, am a french fry professional.
I have been making, eating and gorging myself on theses sticks of potato deliciousness for as long as I can remember. In high school I ate so many of them at lunch that at the end of the year I threw up a ball of grease. So ... clearly ... a professional here whose advice should be followed.
But ... if you're on some sort of stupid meal plan, or you're all out of regular potatoes, or you just feel like having something a little different than regular french fries, why wouldn't you cook up some Sweet Potato French Fries?
Because they're soggy messes. That's why. They'll get brown but they don't get crispy.
I've oven baked them, par boiled them and deep fried them and they don't get crispy. They get brown, but not crisp.
Finally, I've figured out how to make crispy sweet potato fries and the best part is you can do them in the deep fryer or the oven! Either way, you'll end up with crispy fries. Guaranteed.
But like with most things, you're more guaranteed if you do them in the deep fryer.
Here's what you need to do to create this perfect sweet and spicy lunch or side dish.
Gather your sweet potatoes.
Get some corn starch.
Also get some olive oil. Just the cheap stuff. Not the good stuff like my favourite Lorenzo No.5. Seriously best tasting olive oil ever.
Peel your sweet potatoes. I have used the same brand of vegetable peeler for 15 years now. It's the cheapest, most basic vegetable peeler around and it's pretty much every cook's favourite. It's the Great Lash mascara of the vegetable peeling world.
Cut your sweet potatoes until they're a medium thickness. Not hugely thick cut and not shoestring.
Let potatoes soak in water for an hour - half the day. (not mandatory, but recommended)
Preheat oven to 425°
Throw a Tablespoon or two of cornstarch into a plastic bag.
(update: I'm reducing this to a definite 1 Tablespoon of cornstarch because people were reading this as 1 to 2 to 173 Tablespoons of cornstarch. So it's a hard 1 Tablespoon now. Got it?)
Dump a handful of sweet potatoes into the bag with the cornstarch. You don't need to dry them with paper towels or anything. Just drain the water and then give each handful you drop in the cornstarch a good shake. Twist the top of the bag so it forms a balloon with some air inside and shake the fries around until they're lightly coated with the cornstarch. This is important. Too much water and too much cornstarch and you'll end up with a goopy mess. Plus your fries will taste like cornstarch.
Put them on a non stick cookie sheet. The darker the cookie sheet the better - all the better to brown with.
Drizzle 2 Tbsps. of olive oil over the sweet potatoes. This is if you want to be healthy.
Any vegetable oil will work. I've used sunflower, avocado, vegetable etc. etc.
Saturated and Unsaturated Fats
Saturated Fats for frying
- Lard
- Tallow
Monounsaturated & Polyunsaturated Fats for frying
- Olive Oil
- Canola Oil
- Peanut Oil
- Sunflower Oil
You can use as much oil as you want.
(Update: The more oil you use the easier time you'll have of getting the fries crispy but the less healthy they will be.)
I usually go the totally unhealthy route to make sure the fries are crispy. Just drizzle the oil across them and then mix them up with your hands to coat well.
Spread the whole mess out evenly on your baking sheet.
Arrange them so they have space between each fry. The less of them on the pan the better they'll cook. Too many shoved together and they'll never get crispy. They'll just steam. So do NOT overcrowd the pan. Pop the pan into your preheated oven and cook for 15 minutes.
Meanwhile you can make the dipping sauce. Mix together ½ cup of mayonnaise with 1 teaspoon of Sriracha sauce and ¼ teaspoon of Cayenne Pepper.
You can adjust the proportions to taste. Mix it up and taste it then adjust as you like.
Check them after 15 minutes, flip them over (you might have to use a spatula depending on how "non stick" your pan is) and return to the oven if necessary for another 5 minutes. The timing really depends on the size of your fry, the heat of your oven and how well your pan conducts heat.
(update: You can see the pan I'm using here is very dark, this very dark, old, used pan cooks things faster and crispier. So if you have an old pan like this use it. If you have a shiny, new baking sheet your fries will take much longer to cook, will have a greater tendency to stick and won't get as crispy)
Maxwell Williams French Fry and dipping cup!!
If you prefer your food deep fried, (and who doesn't) throw them in the deep fryer at the highest setting for a few minutes instead of sticking them in the oven. You STILL need to coat them in cornstarch. Even in a deep fryer, sweet potatoes fries won't want to get crispy unless they have a coating of cornstarch.
This is how I do them when I'm in a rush. They're always crispier than those from the oven, but far less healthy.
Ingredients
- 2 large sweet potatoes
- 1 Tablespoon of cornstarch
- *Dipping Sauce*
- ½ cup mayonnaise
- ¼ tsp. cayenne pepper
- 1 teaspoon or more Sriracha sauce
Instructions
- Preheat oven to 425 or deep fryer to highest setting
- Peel sweet potatoes, slice into medium thick slices (closer to thin than thick).
- Soak potatoes at least 4 hours in water.
- Drain water from sweet potatoes and shake dry with your hands.
- Put 1 Tablespoon of cornstarch into food safe plastic bag.
- Dump sweet potato fries into bag, blow some air into it, and shake bag until fries are coated.
- Place fries on cookie sheet, drizzle with a couple Tablespoons of olive oil.
- Toss fries until evenly coated with oil.
- Arrange on cookie sheet(s) with lots of space in between fries to prevent steaming.
- Cook in hot oven for 15 minutes then check.
- The fries will release from the pan when they're ready to flip the same way a steak would.
- Flip fries, and continue to cook for another 5-10 minutes.
- (cooking time depends greatly on the quality of your baking sheet so keep an eye on them)
- Dipping Sauce: Mix together mayo, pepper and Sriracha sauce. Adjust to your taste.
Notes
- Do NOT use too much cornstarch. It will lead to heartache and raw, powdery tasting fries.
- A dark, metal baking sheet will give the best results.
- Sweet Potato Fries will get dark fast because of their high sugar content. Don't forget to flip and turn them.
TIPS
- Do NOT use too much cornstarch. It will lead to heartache and raw, powdery tasting fries.
- A dark, metal baking sheet will give the best results.
- Sweet Potato Fries will get dark fast because of their high sugar content. Don't forget to flip and turn them.
Please note : This recipe does have a bit of a learning curve. It may take a few attempts to get your proportions of corn starch and oil correct. It took me several years to figure out how to do this, but with these instructions it shouldn't take you more than a couple of tries.
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Pat
Have made these several times since i first posted last October. Perfect every time!! Everyones loves them. Thank You!
Barbara
Followed this recipe precisely and they weren't good. I cooked them in a gas convection oven and they never got crisp. Let them cook longer and they were either limp or burnt. My pig liked them, though!
Linda
I make a wicked jerk spice and I mix that with the mayo... awesome!
tony saseech
Hi Karen, awesome recipe just one question
after i shake the sweet potato in the corn starch do i have to coat them with olive oil?
Or can i just throw them right into the deep fryer?
Karen
Right in the deep fryer Tony! You only need the olive oil if you're going to oven bake them. ~ karen!
Beth Bilous
Mine came out soggy too. I followed the instructions exactly, and space between each fry. Still came out, and everyone complained. I won't make these again, and stick with good ole white potato fries.
Karen
Beth - Try them once again. It's entirely possible you just didn't cook them long enough if they were soggy. The cook time really depends on the fry and the oven. Also soaking them really does make a difference. Potatoes (sweet and regular) contain starch which helps to bind water to them. When you soak them in water, the starch is released, therefore helping the potato release water. And if all else fails deep fry them (you still need the cornstarch). At the very least just make the sauce and eat it with your fingers. ~ karen!
Lisa Spears
why do you soak the potatoes?
Karen
Because soaking the fries in water leeches some of the starch out of the potatoes. Starch causes the sweet potato (or any potato) to hold onto water. If you et rid of the starch before cooking it, you get rid of more water while cooking it, resulting in crispier fries. ~ karen
Pat
First time and perfect!
Kelly
These were delicious and turned out crispy for me! It was even the first time I tried it! I really think the dark baking pan had everything to do with it. I used a baster to spread my oil over each fry and definitely wasn't skimpy with the canola oil I used. I definitely could have even flipped mine sooner than 15 min, the undersides got a tad dark, but were still super tasty.
I took them out at savored them after the first 15 in. They were excellent dipped in my own concoction of real mayo and a packet of mild sauce from Taco Bell :) Also, for a sweeter taste, they were great in honey. Thanks for sharing!
Karen
Excellent! I'm glad they worked out. If you can handle heat, try adding some cayenne pepper to the sauce next time. It does a good job of cutting the sweetness of the fry. :) ~ karen!
Kelly
I nay have missed it in your original post, but it might be helpful to put "use darkest cooking sheet available to you" as a tip. Found it in the comments but it took a bit. For us amateurs, that detail is probably important. Looking forward to trying this recipe tonight!
Karen
Hi Kelly! You're right, the darker, more used the pan the better for getting pretty much anything crispy and browned. So whenever you clean your cookie sheets don't worry about scrubbing them until they're new looking! It's better if they show their wear and tear. :) ~ karen
Jane
Lol…I can still hear my best friend…fries and gravy please…Woodwards cafeteria. I had to check out your post since I have never succeeded in making them crispy. Tonights menu kale salad topped with oranges/almonds/homemade dressing…and fries!!
Karen
Hi Jane! The deep fryer is definitely the way to go for super-crispy but oven works too. You just have to be careful not to crowd the pan, and not use a lot of cornstarch. Just a light coating. ~ karen!
jainegayer
My cut sp's have been soaking in water all afternoon. Can't wait to try these. Karen, you've never steered me wrong before, so here goes!
Karen
Remember. Don't crowd them on the pan! (if you're doing oven fries) And don't use too much cornstarch. You hardly need any! Good luck and I'm praying to the lord above that you also made the dipping sauce. ~ karen!
jainegayer
No sriracha sauce in the house which surprises me because my husband has hot sauces with devils on the bottles. Would chilpotle sauce work?
Jennifer
Hi Karen! I'm making these tonight...can't wait to see how they turn out!! I wanted to add some seasoning/spices to them. Should I add it to the corn starch or sprinkle over the fries and mix with the olive oil? Do you think adding spices will affect the cooking process at all?
Thanks in advance!!
Oskar
Holy fudge, I love French Fries. Problem is, I'm on AIP paleo now, so I can't eat them anymore. Unfortunately, this means any form of corn starch is out as well, so I will have to find some other solution in order to make this recipe. Thanks anyway
nicolthepickle
I feel like I HAVE to comment on this post because of all the failed sweet potato fries that people have been commenting about.
My recipe is the same as yours and sometimes it works and sometimes it doesn't...Why? I don't know. I make them often and they're not always equally crisp. I think it's the sweet potatoes.
mash
Hi! I love sweet potato fries and these look perfect!! I will be trying them but just wanted to know, because the recipe doesnt really specify. At the beginning you said, you put a tablespoon or two of cornstarch and then throw a handful of SP fries and shake. But in the written recipe, you said put 2/3 tbsps of cornstarch and put all the fries in... does it matter?
Karen
Hi Mash. It's hard to say because sweet potatoes are so different in size and everyone's "handful" is different. Personally, I put around 2 Tablespoons of cornstarch in the bottom of a bag and then throw all of my sweet potato fries (2 sweet potatoes worth usually) into the bag and shake them up. If they're too wet they'll attract too much cornstarch so shake the wet off the fries first. The key is for the fries to be coated with cornstarch but not a thick coating. Just light. Good luck! ~ karen
Anon
I tried this recipe twice -- once fried and once baked. The fried batch were inedible because too much cornstarch stuck to them. The baked batch never got crispy, despite the pan being no more crowded than in the blog pics. The recipe is NOT guaranteed. Finally, I refuse to give my name or email address because Karen is clearly a rude bitch with people who say her recipe doesn't work.
Karen
Awwww. You sweet talker you. K. You have already admitted to using too much cornstarch in your own comment. A I a bitch? Maybe. But I'm not a coward, mr. / ms. Anonymous. - karen!
Harold Jones
I know this an old post but I have actually made these using the oven only method and passed the technique to others because they're crisp and delicious done IF just right; you really have to be careful about the prep part. Too wet into too much cornstarch and they suck I know.
Tonight I had the balance perfect but dinner got put off for a few hours. So I'm sitting here with a bag of lightly coated fries and waiting. For a lark, I pan fried a few until done; they're beyond yummy. So I'm thinking that perhaps doing a quick "pre fry" before oven baking might satisfy all the naysayers (as long as they don't put too much CS in the bag--dust only or total gummy fail). I have yet to oil up these fries for the oven but I doubt after sitting for a few hours waiting they'll be quite as tasty. But who knows?
Made properly, these rock! Thanks for the recipe.
Hope
Mine didn't crisp... but i didn't read the part about not cramming too many onto the pan. They definitely steamed themselves!
IsaMarie
I just finished eating my first batch of these. I can't even put into words how heavenly that experience was. These were better than any restaurant or momma's sp fri. A few were overcooked and a few undercooked, but oh my goodness, they were so good!! I dipped them in a ketchup, sriracha, cilantro sauce. Ahhh, I'm in love. So much love.
Mandy
You are my new hero! I can't tell you how many times I've tried to make homemade sweet potato fries and failed. I followed the directions exactly and baked them in the oven - they turned out perfect! They're almost like candy. YUMMERS!!!!
Karen
That's great Mandy. Thanks for letting me know! ~ karen