All-purpose flour - 1 cup + 1 tablespoon (150 g)
1 tbsp (10 g) Cornstarch
1/8 tspBaking powder
1 tspSalt
Milk - 1/2 cup + 1 tablespoon (130 ml)
1 1/2 tspVinegar
3/4 cup (173g)Unsalted butter
3/4 cup (150g)Brown sugar
3/4 cup (150g)White granulated sugar
Unsweetened cocoa powder - 1/2 cup + 1 tablespoon (57 g)
1 tspInstant coffee powder
1/2 cup (100 g)Chocolate chips or chunks
100 gmsWalnuts or pecans: chopped (optional)