Sift together 1 1/2 cups all-purpose flour, 1 1/2 cups granulated sugar, 1 tsp baking soda, and a pinch of salt into a bowl, then mix well.

In another large bowl, melt 1 cup butter and 4 oz of dark chocolate in the microwave (about 45 seconds, stir, then another 30 seconds). Stir until smooth.

Mix in 1 cup of cocoa powder.

Add 1 cup of milk, 1/2 cup of oil, 4 eggs, 1 tsp vanilla extract, and 3 tsp of vinegar. Stir until smooth.

Add the dry ingredients and mix until there are no lumps.

Pour the batter into the liners, filling them just over 3/4 full.

Bake for 18–20 minutes, until a toothpick comes out clean.

Take them out of the pan and let them cool on a rack.

Once cooled, frost with your favorite frosting and add sprinkles if desired.