This chocolate cake recipe has been "the" chocolate cake in our family for decades, for two big reasons. First, it is the best-tasting chocolate cake in my family's (considerable) baking repertoire, moist and deeply chocolatey without being heavy. Second, sheer ease. This cake has exactly two steps: mix all the ingredients together in a bowl, and bake. I've cheated on my mom's recipe by adding instant espresso powder—a baking trick that heightens the flavor of chocolate—but feel free to leave it out. Classic chocolate frosting works well if you want to gild that chocolate lily, but we prefer to frost this cake with homemade, lightly-sweetened whipped cream.
Note: A few hours at room temperature will be fine, but unless stabilized with gelatin, whipped cream frosting like this will "melt" over time. So make sure the cake has fully cooled before applying it to your cake—and don't frost the cake too far in advance or you will have to hold the cake in the fridge.
Preheat the oven to 350° F and grease two 8-inch cake pans or line the cupcake tins.
Add all the ingredients to the bowl of an electric mixer fitted with a paddle attachment. Mix on low, and then on medium, for about three minutes, until the batter is smooth. Scrape the bowl to make sure the cake batter is fully mixed. This can also be done by hand with a spatula until the batter is smooth and the ingredients fully incorporated.
Divide the batter between the cake pans and bake until the center of the cake springs back lightly when pressed and a cake tester comes clean, about 30 to 35 minutes for 8-inch cake layers.
Whipped cream frosting
Add the heavy cream to the bowl of an electric mixer fitted with the whisk attachment. Extra points for chilling the bowl first—keeping the cream as cold as possible makes it whip better and adds stability.
Starting on low to medium-low to prevent splashing, increase the speed to medium high and whip the cream until it thickens slightly. Add the confectioner's sugar and vanilla. Continue to whip, checking often, until the whipped cream just barely comes to stiff peaks and holds its own shape. Do not over whip. (If the whipped cream looks grainy or chunky, it has over-whipped.)
Layer, fill, cover and decorate the cake as you like!