Hazelnut dacquoise cake with chocolate mousse and espresso whipped cream

Tada, cake #3! I'd planned to make the daquoise from the Flour cookbook (shown pictorally here), but then I realized that this hazelnut cake was the same idea but faster and more cake-like. The cake only has a smidge of flour, so it might be adaptable into something the gluten-free bride can consume! But I did my best to follow the recipes this time, at least for the cake. Leaving the raw egg white out of the mousse resulted in dense, almost truffle-like filling.

This cake was barely tall enough to consider slicing in half when baked in a 9" pan—apparently my folding-in-egg-whites skills are a few notches below smittenkitchen's. And, although I did successfully slice it into two flat and even halves, I was not able to successfully place the top layer on the mousse without it breaking. Luckily the whipped cream covered up my mishaps. The flavors go together beautifully, but I think the dacquoise is too finicky to make for the wedding itself.

cake:
5 oz hazelnuts
2 sticks butter (preferably unsalted, but I had 1/2 stick unsalted and the rest salted)
1/2 vanilla bean
1 1/3 c powdered sugar, plus extra for dusting the cake
1/3 c flour
6 large egg whites
3 T sugar

Preheat oven to 350F, and butter and parchment a 9" springform pan.

Toast the hazelnuts on a baking sheet for 12 minutes. Dump onto a clean dishtowel, fold the towel up into a nice little package, and roll your palms around on the towel to rub off the hazelnut skins. It's like a warm massage for your hands.

Put the butter, the scrapings out of the vanilla bean, and the vanilla bean itself in a medium saucepan. Cook over medium-low heat until browned, stirring frequently after it started to foam. Remove the vanilla bean and let cool.

Transfer the hazelnuts, sans skins, into the bowl of the food processor. Add the powdered sugar and grind until fine, then add the flour and pulse to combine.

Separate the egg whites into the bowl of the stand mixer. Beat with the whisk attachment until just shiny, then with the mixer still running slowly pour in the sugar. Beat until the meringue holds very stiff peaks. Fold in the butter and dry ingredients extremely carefully in small alternating batches. (I opted to err on the side of leaving some small egg white chunks in the batter instead of on the side of extra deflating, which resulted in a few unappealing egg white spots in the finished cake.) Pour into the prepared pan and bake for 40 minutes until browned and a tester comes out clean. Cool in the pan for 20 minutes, then invert onto a wire rack and let cool completely (1 hr).


mousse:
3 T butter
4 oz TJs pound plus dark chocolate, chopped
2 T Drambuie
1/2 c cold whipping cream

Melt the butter and chocolate together in a double boiler equivalent, then stir in the Drambuie and let cool. Whip the cream until it holds soft peaks, and gently stir the cream into the chocolate. Let sit on the counter for up to an hour until it's time to assemble the cake; it will set up within a minute or two.


whipped cream frosting:
2/3 c cold whipping cream
3 T powdered sugar
1/2 t vanilla
pinch allspice
1/2 t espresso powder

Whip the cream until it holds soft peaks, then whip in the other ingredients until holds not quite firm peaks and the espresso powder is dissolved. Stick in the fridge until assembly time.


assembly:
Place the cake, flat side down, back on the base of the springform pan. Slice the cake in half with a serrated knife, even though it's not very tall, and set the top half aside. Spread the mousse on the bottom half of the cake and top with the top half of the cake, then spread the whipped cream on top. Carefully put on the sides of the springform pan, cover with plastic wrap, and put in the fridge overnight.