2 sticks unsalted butter
1 stick unsalted butter; for pan
8 ounces bittersweet chocolate chips
1 1/4 cups all-purpose flour
1 teaspoon baking powder
pinch salt
4 large eggs
2 cups sugar
2 tablespoons amaretto liqueur
1 1/2 cups walnuts
powdered sugar; for garnish

1. Preheat oven to 350 degrees F.

2. Line a 9 by 9 square baking pan with parchment paper, making sure paper hangs over the edges. Grease paper with butter so the brownies don't stick. Melt butter and chocolate over a double-boiler and stir gently until smooth and shiny. Remove from the heat and cool slightly.

3. Sift together flour, baking powder, and salt into a mixing bowl and set aside. Whisk together eggs, sugar and amaretto in a mixing bowl until combined. Pour in chocolate mixture and continue to whisk until combined. Gradually add flour mixture, then add walnuts and incorporate with a wooden spoon. Transfer batter to baking pan and bake for 40 to 45 minutes or until a cake tester comes out clean when inserted into the middle of the pan. When done, invert onto a cutting board, remove paper and cut into squares. Garnish with powdered sugar and serve.