Midnight Chocolate Cake with Milk Chocolate Buttercream

This is the chocolate cake to end all chocolate cakes: moist, velvety, and melt-in-your-mouth-tender, with deep, pure chocolate flavor and a smooth, silky frosting that tastes like the best milk chocolate bar has been melted down, whipped up, and spread all over. I baked my way through dozens of cookbooks, combining the best qualities of each recipe, and this cake was born. It’s the easiest method for mixing a cake that I know. The batter holds for up to a day, so if you are short on time,