Peanut Butter-Cocoa Brownies

3/4 cup butter or margarine
3/4 cup creamy peanut butter
1 3/4 cups granulated sugar
2 teaspoons vanilla extract
4 eggs
1 1/4 cups all-purpose flour
1/2 teaspoon baking powder
1/4 teaspoon salt
1/4 cup cocoa

Heat oven to 350 degrees F. Grease a 13 x 9-inch baking pan.

Melt butter. Add peanut butter; stir until peanut butter is melted. Stir in sugar and vanilla extract. Add eggs; beat well with spoon. Add flour, baking powder and salt; beat well. Remove 1 3/4 cups batter; stir cocoa into this part. Spread chocolate batter into prepared pan. Spread remaining batter over top. Bake 30 minutes or until brownies just begin to pull away from sides of pan.

Cool completely in pan on wire rack. Cut into bars.

Makes about 36 brownies.