Why This Recipe Works
The technique for our chocolate-hazelnut cake recipe was straightforward: In a mixer, we creamed the butter and sugar and added egg yolks, followed by melted chocolate and ground hazelnuts. We then whipped egg whites and folded them in, transferred the batter to a springform pan (for easy removal after baking), and slipped the pan into the oven. After several rounds of testing on our chocolate-hazelnut cake, we noted that the texture and crumb of the cake was largely determined by the quantity and texture of the nuts. We preferred the more refined texture of the cake made with toasted finely ground nuts, ground in a food processor along with some sugar to prevent the nuts from clumping.