1. Preheat oven to 350°. In a large bowl, sift together flour, baking powder, salt, 1 1/3 cups granulated sugar, and 1/4 cup cocoa. Make a well in center. In a medium bowl, beat milk, 1 tablespoon amaretto, vanilla, and melted butter with a fork to blend well. Pour liquid ingredients into well in dry ingredients and stir with fork until well blended. Pour batter into a buttered 8-inch square baking pan. Using a rubber spatula, smooth top; set aside.
2. In a medium saucepan, combine remaining 3/4 cup granulated sugar, 1 1/2 cups cocoa, 2 tablespoons Amaretto, brown sugar, and coffee. Stir with a wooden spoon over low heat until sugar and cocoa are melted, 2 to 3 minutes. Remove from heat and pour over ingredients in pan.
Bake 30 minutes.