kimr 1 Review Links Ratings & Reviews 1 Chef John's Truffled Potato Gratin 06/10/2018 This is the best potato’s au gratin I’ve ever had! I added a little shaved sweet onion in the layers with the mushrooms. Because of the comments about it being too milky or liquidy I made a roux with butter and flour then added the cream and dissolved the cheese in that. It was a little thick so I diluted with some chicken broth and then poured a little over each layer as I went. Cooked for 1 hr 15 min then added the extra cheese on the top with some Panko. Under the broiler for about 5 min and this came out perfect. Better than any fancy restaurants! The sottocerene was amazing in this. I also added a little Gruyere cheese too. Soooo good! Thank you Chef John!!!?? Helpful (4)