From America's Test Kitchen Season 5: Four-Star Desserts
A common restaurant dessert, volcano cake, or molten chocolate cake, is an intensely chocolate cake that boasts a warm, liquid center. In addition to its great flavor and alluring contrasting textures, the cake can often be made ahead and baked just before serving. The make-ahead appeal of such a cake inspired us to master this dessert for the home cook.
The initial recipes we tried revealed a host of problems with this cake—unbalanced chocolate flavor and a soggy or dry texture were just a few issues we faced. After testing various chocolates, we settled on a combination of bittersweet chocolate and unsweetened chocolate—this gave us maximum chocolate flavor. Chocolate alone seemed a little flat, so we added Grand Marnier for another layer of flavor. Whole eggs and egg yolks contributed richness and cornstarch helped make the batter remarkably stable. To help the cakes fall right out of the ramekins without a struggle, we buttered and sugared the ramekins before pouring in the batter. The cakes alone were great, but we felt they were even better when accompanied by a cold, creamy scoop of doctored “espresso” ice cream.
Use a bittersweet bar chocolate in this recipe, not chips -- the chips include emulsifiers that will alter the cakes texture. The cake batter can be mixed and portioned into the ramekins, wrapped tightly with plastic wrap, and refrigerated up to 24 hours in advance. The cold cake batter should be baked straight from the refrigerator.