If you love to pick the crunchy crumb topping off of baked goods, this ice cream cake is for you. One batch of crunchies—richly flavored with Dutch-process cocoa powder and espresso powder—is used three ways: pressed into a crust to add structure, folded into vanilla ice cream for a dreamy cookies-and-cream filling, and scattered across the cake as a Flintstones-like pebbly topper. Feel free to swap in another ice cream flavor if vanilla isn’t your speed; chocolate and coffee are obvious top contenders.
Ingredients
10–12 servings
Crust and Crunchies
2
1⅓
1
1
1
1
1
Fudge and Assembly
¾
¾
⅓
⅓
1
¾
½
3
Preparation
-
Crust and Crunchies
Step 1
Place a rack in middle of oven and preheat to 350°. Cut a piece of parchment into an 11″ square. Place on the base of a 9″-diameter springform pan, attach sides of pan (the sides of the parchment will stick out). Whisk 2 cups (250 g) all-purpose flour, 1⅓ cups (267 g) granulated sugar, 1 cup (100 g) Dutch-process cocoa powder, sifted, 1 tsp. instant espresso powder, and 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt in a large bowl to combine. Drizzle in 1 tsp. vanilla extract, then add 1 cup (2 sticks) chilled unsalted butter, cut into small pieces, and work into dry ingredients with your fingers until mixture resembles wet sand (it should hold together when squeezed).
Step 2
Place one third of mixture in prepared pan and, using a flat-bottomed measuring cup, pack into an even layer across bottom of pan. Using your hands, form remaining mixture into pieces of various sizes by squeezing bits together. Scatter over a parchment-lined rimmed baking sheet. Bake both on middle rack until crust is set and crunchies on baking sheet are cooked through (a little butter will leak out and that’s okay), 18–22 minutes. Let cool.
-
Fudge and Assembly
Step 3
Place ¾ cup semisweet chocolate chips in a medium heatproof bowl. Heat ¾ cup heavy cream, ⅓ cup (33 g) Dutch-process cocoa powder, and ⅓ cup (67 g) granulated sugar over medium-low heat, stirring, until combined and sugar is dissolved, about 4 minutes. Pour over chocolate chips and add 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt, ¾ tsp. instant espresso powder, and ½ tsp. vanilla extract; whisk until smooth. Let fudge cool.
Step 4
Meanwhile, let 3 pints vanilla ice cream sit at room temperature 15 minutes to soften. Transfer to a large bowl.
Step 5
Divide cooled crunchies in half, moving larger pieces to one side (these will be used for the topping). Set larger pieces aside. Add smaller pieces to ice cream and fold with a rubber spatula to distribute throughout.
Step 6
Scoop half of ice cream over crust in springform pan; smooth into an even layer. Scrape fudge over and smooth into an even layer. Freeze ice cream in pan and remaining ice cream in bowl until fudge is set, 13–17 minutes.
Step 7
Scrape remaining ice cream in bowl over fudge in pan and smooth into an even layer. Top with reserved larger crunchies. Cover ice cream cake with plastic wrap and freeze at least 12 hours.
Step 8
Just before serving, run a knife around edges of cake to help loosen, then release sides of pan and remove. Slide cake onto a cutting board to slice.
Do Ahead: Cake can be assembled 3 days ahead. Keep frozen.
