1/3 cup creamy peanut butter
2 tablespoons butter
3/4 cup sugar
1 teaspoon vanilla
2 eggs
1/2 cup flour
1/4 teaspoon baking powder
1/8 teaspoon salt
1 package brownie mix
20 mini peanut butter cup candies

Combine peanut butter and butter in medium microwave-safe bowl.  Microwave (high) for 45 seconds. Stir until peanut butter is melted. Stir in sugar and vanilla. Add eggs; mix well. Add flour, baking powder, and salt; mix until smooth batter forms.  Spread peanut butter batter in greased 9 X 13 baking pan.  Prepare brownie mix according to package directions. Carefully spread brownie batter over top of peanut butter layer. Using tip of table knife, swirl the two batters together. Bake in 350 degree oven for 15 minutes; remove from oven and press peanut butter cups into top of brownies in four rows of five. Bake an additional 15 minutes or until set. Do not over bake. Cool completely in pan. Cut into squares. Makes 20 brownies.