At Heartland, we use maple syrup in much the same way as we do sorghum syrup. This lovely dessert pairs chocolate with maple syrup to create a mousse that we roll inside chocolate sponge cake to form a roulade. As is standard in pastry kitchens, we weigh the dry ingredients rather than measure them.
This recipe is courtesy of Heartland: Farm-Forward Dishes from the Great Midwest cookbook by Lenny Russo and Burgess Lea Press.
Preheat the oven to 350 degrees F. To make the chocolate sponge cake, whip the egg yolks in a stand mixer until doubled in volume. While the yolks are whipping, bring the maple syrup to the boil in a saucepan over moderately high heat. Simmer until reduced by half. Pour the hot maple syrup in a steady stream into the whipping egg yolks. Whip until cool and set aside.
In a bowl, sift together the flour and cocoa. In a clean mixer bowl, combine the egg whites and sugar and whisk to form soft peaks. Fold one third of the yolk mixture into the egg whites. Fold the flour and cocoa into the egg mixture, and then fold in the remaining egg whites. Line a sheet pan with parchment, and spread the batter evenly over the pan. Bake until set, about 20 minutes.
To make the mousse, melt the chocolate in a bowl set over a pan of simmering water. Place the egg yolks in the bowl of a stand mixer and whisk until doubled in volume.
Bring the maple syrup to the boil in a saucepan over moderately high heat. Simmer until reduced by half. With the mixer running, pour the hot maple syrup in a steady stream into the egg yolks. Transfer to a mixing bowl and fold in the melted chocolate.
In a large bowl, whip the cream to medium peaks, and fold it gently into the chocolate mixture. Transfer the mousse to serving dishes and refrigerate until set.
When the sponge cake has cooled to room temperature, dust the top with sugar and turn it out onto a sheet of parchment. Spread the mousse evenly over the sponge cake. Using the parchment paper, roll the sponge cake into a tight roll. Refrigerate until firm. To serve, use a long serrated knife to slice the roulade to the desired thickness.