Step 1

In a large bowl, cream together 1/2 cup butter or margarine, 1/2 cup peanut butter, white sugar, brown sugar, and vanilla. Add egg and beat well.

Step 2

In another bowl, combine the flour, baking soda, baking powder, and salt. Add these dry ingredients to the creamed mixture. Stir. Add oatmeal and stir.

Step 3

Drop by teaspoons onto greased baking sheet, and press each mound down with a fork to form 1/4 inch thick cookies. Bake at 350 degrees F (175 degrees C) for 10 minutes, or until cookies are a light brown.

Step 4

To Make Filling: Cream 3 tablespoons butter or margarine with the confectioners' sugar, 1/2 cup smooth peanut butter, and the cream. Spread filling onto half of the cooled cookies, then top with the other half to form sandwiches.