Chocolate Peanut Butter Mousse Cake with Peanut Praline and Caramel Sauce

To make cake:

Preheat the oven to 350°F. Spray and flour two 8-inch round pans. In a large bowl, mix together sugar, flour, cocoa, baking powder, baking soda, and salt. Add orange juice, oil, vanilla, and eggs; mix for 2 minutes, or until thoroughly combined. Using a silicone spatula or wooden spoon, gently mix in boiling water, one-third at a time. Mix in chopped peanuts. Divide batter between the two prepared pans and bake for 35 to 40 minutes, or until a skewer inserted into the cakes comes out clean. Let cool in the pan for 10 minutes. Turn the cakes out onto a rack to cool completely.

The cakes may be stored in plastic wrap at room temperature for two days or frozen for up to three months.

To make mousse:

In the bowl of a stand mixer, beat peanut butter and cream cheese together until creamy. Add confectioners’ sugar and vanilla and mix well. In a separate bowl, beat whipping cream until stiff. Fold in whipping cream to the peanut butter mixture, one-third at a time, mixing well after each addition. Cover with plastic wrap, and refrigerate for at least two hours or overnight. Can be made three days in advance.

To make praline:

Line a cookie sheet with parchment or a silicone mat. Place water and sugar in a small heavy saucepan and heat over medium-high heat. Stir just until sugar dissolves, and cook without stirring until mixture starts to color. Add peanuts and stir to coat. The nuts will turn white, but keep mixing until the white parts melt and you see a golden caramel on the bottom of the pan, about five minutes. Remove from heat and spread the candied nuts on the prepared cookie sheet. Let cool. Can be made five days in advance and stored in a freezer bag or airtight container. To decorate the cake, take about three-quarters of the candied nuts and either chop in a food processor or place in a freezer bag and bang with a saucepan or rolling pin. Break remaining peanuts into pieces and eat as candy.

To make caramel sauce:

Place sugar and water in a small heavy saucepan over medium-high heat. Stir to dissolve and then allow to cook without stirring until it turns a deep amber. Add cream and margarine, and whisk well. Transfer into a bowl. Let cool 10 minutes, cover, and place in fridge to cool for one hour. May be made three days in advance.

To assemble cake:

Trim cakes so that the tops are flat and the sides are straight. Slice each cake in half so that you have four layers. Set aside a bottom slice to be the top of the cake. Place the other bottom on a platter. Scoop up and dump about one-quarter of the mousse into the center of the cake layer. Using a silicone spatula in a back-and-forth motion, spread mousse from the center to the sides of the cake, stopping just inside the edge, so you can still see the peanut butter mousse through the chocolate. Place another cake layer on top of the mousse and spread another quarter of the mousse. Repeat for the third layer. For the top layer, place the reserved slice bottom up so that the smooth side is the top of the cake. Spread remaining mousse, stopping ½ inch from the edge, so there is a small chocolate cake border. Refrigerate for 1/2 hour. Drizzle caramel sauce over the top of the mousse and down the sides, zig-zagging back and forth across the cake. Sprinkle the chopped peanut praline over the top and drizzle a little more caramel over the peanuts.

Store in the fridge for up to five days. Freeze for up to three months.