Peanut Butter Fingers

1 1/2 cubes butter
1/2 c. sugar
1 c. brown sugar
1 egg
1 t. vanilla
3/4 t. soda
1/2 t. salt
1 1/2 c. flour
2 c. rolled oats

Mix all but flour and oats. Mix well, then add flour and oats and mix well. Spread in greased cookie sheet. Bake 325° for 10-15 minutes, until slightly brown. Whip 2/3 c. peanut butter, spread on top when it's cool. Cool completely, then make chocolate frosting for top. 

Frosting:

3 c. powdered sugar
1/4 c. cocoa
1/3 c. milk
1/3 c. oil
2 t. vanilla