INGREDIENTS
16 tbsp
unsalted butter, softened
4 oz
unsweetened chocolate (chopped)
1/4 cup
Dutch-processed cocoa
1 1/4 cups
boiling water
3/4 cup
unbleached all purpose flour
3/4 cup
plain cake flour
1 tsp
baking soda
1/4 tsp
salt
1 1/2 cups
packed (10 1/2 oz dark brown sugar)
3
large eggs (room temperature)
1/2 cup
sour cream
1 tsp
vanilla extract
3 3/4 cups
powdered sugar
1/2 cup
butter (1 stick, softened)
3 tbsp
half and half
1 1/2 tsp
vanilla
mini chocolate chips for decoration