Reese's Peanut Butter Cup Cookies

{image from Amy's Finer Things}

1/2 cup butter or margarine-softened
1/2 cup peanut butter
1/2 cup sugar
1/2 cup brown sugar
1 egg
1/2 tsp. vanilla
1 1/4 cup flour
3/4 tsp baking soda
1/2 tsp. salt

40 mini Reese's Peanut Butter Cups

Beat butter, peanut butter, sugar and brown sugar. Add egg and vanilla. In separate bowl combine flour, baking soda and salt. Add to butter mixture. Roll into 1 inch balls. Place in greased mini muffin pans. Bake at 350 degrees for 9 minutes. When done, place peanut butter cup into cookie and press down. Let cool in pan before removing. Yields about 3 1/2 dozen cookies.