This is one of my favorite brownie recipes. It is taken from The Complete Light Kitchen by Rose Reisman.
2/3 cup granulated sugar
1/4 cup vegetable oil
1 tsp pure vanilla extract
1/3 cup unsweetened cocoa powder
1/3 cup all-purpose flour
1 tsp baking powder
1/4 cup low-fat yogurt or sour cream
1/4 cup semi-sweet chocolate chips
1/3 cup light cream cheese
2/3 cup icing sugar
1 1/2 tsp unsweetened cocoa powder
1 1/2 tsp water
Dusting of icing sugar
1. Preheat the oven to 350F. Spray an 8-inch square pan with cooking oil.
2. For the brownies, combine the sugar, oil, egg and vanilla in a bowl and mix well. Add the cocoa, mixing it in well. Add the flour, baking powder, yogurt and chocolate chips, mixing just until combined and smooth. Don’t over mix.
3. Pour the batter into the prepared pan. Bake in the center of the oven for 15 to 20 minutes, just until set. Do not overbake. Cool on a rack for 15 minutes before icing.
4. To make icing, place cream cheese, icing sugar, 1 1/2 tsp cocoa powder and water in a blender or food processor and process until smooth. Spread over the top of the brownies.
5. Cut into squares and garnish with a dusting of icing sugar, or drizzle melted dark and white chocolate overtop.