Streuselkuchen (German Crumb Cake) vs Mousse au Chocolat: Velvety French Chocolate Delight

Both desserts lean on sugar, butter and eggs, yet they put them to opposite uses. Streuselkuchen is a baked cake: a risen yeast dough enriched with a single egg and softened butter, covered with coarse crumbs of cold butter rubbed into flour and sugar and baked until golden brown. Mousse au chocolat instead melts its butter with dark chocolate and separates four eggs, whisking the yolks with sugar and beating the whites to stiff peaks. The result is a light, airy, chilled dessert with deep chocolate flavor, in contrast to the cake's buttery, crumbly bite.