Chocolate Cake with White Chocolate Frosting

Course: Dessert

Cuisine: American

Keyword: Chocolate Cake, Chocolate Cake with White Chocolate Frosting

Servings: slices

Preheat the oven to 350F (180C). Lightly grease a 9x13 inch (23x33 cm) pan and dust with cocoa powder.
In a large bowl, sift together the flour, cocoa, baking soda, baking powder and salt. Add in the sugar and whisk together until evenly combined.
In a separate bowl, whisk together the oil, eggs, vanilla, milk and sour cream until you no longer see lumps of egg. Whisk the hot coffee into the bowl.
Add the wet ingredients into the dry ingredients and beat together on a low speed for about 1 minute or whisk by hand until smooth. The batter will be thin.
Pour into the prepared pan. Bake in the middle of the preheated oven for about 30-40 minutes, or until the the top looks set and an inserted toothpick comes out clean or with a few damp crumbs but not gooey cake batter. If you're unsure if the cake is done baking, I recommend continue baking for a few extra minutes because the cake is unlikely to dry out.
Remove from the oven and cool fully in the pan.

If using chocolate bars or chocolate baking squares, first finely chop the chocolate. Place in a heatproof bowl.
If using the microwave, microwave for 1 minute on medium power - I used 50% power (do not high power, which is often the default). Remove from the microwave and stir. Continue microwaving for 30 second intervals, stirring between each until smooth. If using a double boiler, place heatproof bowl over a saucepan with about 1/2 to 1 inch of gentling simmering water over low heat. Ensure that the water doesn't touch the bottom of the bowl. Gently stir the chocolate as it melts.
Allow the chocolate to cool for at least 15 minutes.
In a large bowl, beat the butter until smooth. Add in 2 cups sifted powdered sugar and the salt. Beat together, starting with the mixer on a low speed and gradually increasing to medium speed. Mix in the cooled white chocolate. Ensure that it isn't warm, otherwise it will melt the butter. Occasionally, turn off the mixer and scape down the sides and bottom of the bowl. Beat in the whipping cream 1 tablespoon at a time, until the desired thickness and flavor is reached.
Frost the cooled cake with the back of a spoon or an offset spatula.

Buttermilk: If you don't have buttermilk, add 2 teaspoons of distilled vinegar or freshly squeezed lemon juice to 2/3 cup milk. Whisk together and let it sit for 5 minutes before using.
Coffee: Can be substituted with almost boiling water.
White Chocolate: Use high quality white chocolate. Do not use chocolate chips labeled "white cream", any white chocolate that feels waxy, or candy melts.
Storage: Store leftovers in an airtight container at room temperature for up to 2 days or in the fridge for up to 4 days. If the frosting is in the fridge, it will harden. I recommend taking the cake out of the fridge about 1 hour before enjoying so that the frosting can soften.
Nutrition: Details provided are an estimate only based on 1 slice, assuming the cake is sliced into 15 uniform slices. This cake is very rich, so likely you can get 18 slices or more.