4 squares BAKER'S Unsweetened Baking Chocolate
1/2 cup (1 stick) butter or margarine
1 cup granulated sugar
1 cup firmly packed brown sugar
2 eggs
1 cup BREAKSTONE'S or KNUDSEN Sour Cream
1 tsp. vanilla
1-1/2 cups flour
2 tsp. CALUMET Baking Powder
1/4 tsp. baking soda
1 cup finely chopped PLANTERS Walnuts, lightly toasted (optional)



GREASE and flour 8x4-inch loaf pan.
MICROWAVE chocolate and butter in large microwavable bowl on HIGH 2 minutes or until butter is melted. Stir until chocolate is completely melted.
ADD sugars to chocolate mixture; mix well. Blend in eggs, sour cream and vanilla. Add flour, baking powder and baking soda; mix well. Stir in walnuts. Spread into prepared pan.
BAKE at 350°F for 60 to 70 minutes or until toothpick inserted in center comes out clean. Cool in pan 10 minutes; remove from pan. Cool completely on wire rack