INGREDIENTS
1 cup
unsalted butter (2 sticks, or 8 ounces, or 227 grams) each halved
7 oz
72% cacao or more dark chocolate, chopped or broken coarsely (I used Ghiradelli Twilight Delight)
2 cups
(14 ounces, or 397 grams) granulated sugar
1/2 cup
(2 ounces, or 57 grams) Dutch processed cocoa powder (I recommend Cacao Barry Extra Brute or Pernigotti)
1 1/4 cups
strong hot coffee or hot water plus 1 tablespoon espresso powder
1 tbsp
vanilla extract
3
large eggs
2 cups
(10 ounces, or 284 grams) all-purpose flour
1 tsp
baking powder
1 1/2 tsp
baking soda (sodium bicarbonate)
1/2 tsp
salt
1/2 cup
(4 ½ ounces, or 128 grams by weight) sour cream
1/2 cup
(3 ½ ounces, or 100 grams) granulated sugar
1/2 cup
by weight, or 150 grams) corn syrup
1 tbsp
vanilla extract
1 1/2 cups
(12 ounces, or 3 sticks, or 340 grams) unsalted butter, softened
1 cup
(3 ½ ounces, or 100 grams) Dutch processed cocoa powder
4 cups
(16 ounces, or 454 grams) powdered sugar