Frosted Peanut Butter Fingers!

Frosted Peanut Butter Fingers
1 cup butter, softened
1-1/2 cups packed brown sugar
1 cup sugar
2-1/2 cups creamy peanut butter, divided
1 egg
1-1/2 tsp vanilla extract
2-1/2 cups oatmeal quick cooking oats
2 cups flour
1 tsp baking soda
½ tsp salt

Chocolate frosting:
6 TBSP butter, softened
4 cups powdered sugar
½ cup baking cocoa
1 tsp vanilla
6-8 TBSP milk

Cream butter and sugars. Add 1 cup peanut butter, egg, and vanilla. Mix well. Combine oats, flour, baking soda, and salt. Add to creamed mixture. Spread into a greased cookie sheet. Bake at 350 for 13-17 minutes or until golden brown. Cool slightly on a wire rack; about 12 minutes. Spread with remaining peanut butter. Cool completely. Make frosting, spoon over peanut butter layer, cut and serve.