Guinness, Chocolate, and Caramel Tart

1. Preheat the oven to 350 degrees F (175 degrees C). Lightly grease a 9-inch tart pan with a removable bottom.

2. Mix pretzel crumbs, brown sugar, melted butter, and salt together in a bowl until mixture resembles wet sand. Pour into the tart pan, and press very firmly and evenly up the sides and into the bottom of the pan.

3. Place tart pan onto a baking sheet and bake until crust is golden brown, 10 to 15 minutes. Allow crust to cool completely in pan, about 30 minutes.

4. Combine heavy cream, butter, vanilla extract, and salt in a small saucepan over medium-low heat and cook until butter is melted and mixture begins to bubble, 3 to 5 minutes. Remove from heat, set aside, and keep warm.

5. Combine sugar, corn syrup, and water in a large light-colored saucepan with high sides. Cook over medium heat, swirling occasionally, until mixture is amber in color, 10 to 12 minutes. Reduce heat to low, and very carefully whisk in reserved cream-butter mixture, as caramel mixture will bubble up and steam; stir constantly.

6. Insert a candy thermometer into the mixture and cook over low heat, stirring occasionally, until caramel reaches 245 degrees F (118 degrees C), 25 to 30 minutes. Carefully pour caramel into an even layer in the baked and cooled crust. Allow caramel layer to cool until set, 1 to 2 hours.

7. Prepare the chocolate layer. Pour stout beer into a saucepan and bring to a boil over medium-high heat. Cook until stout has been reduced to 1/4 cup, 20 to 25 minutes. Pour reduced stout into a large bowl. Stir in chopped chocolate, chocolate chips, butter, and vanilla; set aside.

8. Heat cream in a small saucepan over medium-low heat until just simmering, 3 to 5 minutes. Pour over chocolate and allow to sit for 5 minutes. Stir until chocolate is completely melted and smooth. Carefully pour melted chocolate over the cooled caramel layer, making sure not overflow the pan.

9. Use a toothpick to pop any air bubbles that may arise. Allow chocolate layer to cool and set up completely, 1 to 2 hours.

Cook's Notes:

The brand of pretzels used in the crust matters, as some are saltier than others. I used Rold Gold, which were not that salty, thus I added extra salt to the crust for a better sweet-salty balance. If your pretzels are saltier, you may not need the added salt. Adjust to taste. Also make sure that the pretzels are crushed very fine (I ran them through a food processor to achieve this) or it will be difficult to press the crust into the pan.

Make sure to use a candy thermometer for the caramel. It needs to reach approximately "firm ball stage" at 245 degrees F (118 degrees C). This allows the caramel to set up firmly, but still be soft enough to eat. However, a softer caramel may be achieved by cooking it only to "soft ball stage" at 240 degrees F (115 degrees C), though this may not set up as nicely as a layer. The time it takes to reach this temperature can vary substantially, so be sure to use the thermometer for accuracy.

You will probably have extra chocolate that won't fit; only pour as much as needed to fill the tart shell and cover the caramel without overflowing the pan. Save the extra for another use.

It's important to serve this tart at room temperature, as the caramel hardens substantially when chilled. This tart may be made up to several days in advance, as long as it is kept chilled; but be sure to bring it back to room temp before serving. For easier cutting, run a sharp knife under hot water, then dry it off on a towel. The warmed knife should allow for easier and cleaner cuts.