Cream together:
1/2 cup peanut butter
1/2 cup butter or margarine
1/2 cup brown sugar
1/2 cup sugar 
1 egg
1 tsp. vanilla

Stir together:  
1 cup flour
1/2 tsp.soda
3/4 tsp.salt
1 cup oatmeal (quick oats)
Combine with creamed ingredients.

Press into a 9 X 13 ” pan.  Bake at 325 for 10 minutes, probably a little longer if you use butter, maybe more like 12 or 15.  Spread with 3/4 cup chocolate chips, more if necessary to cover nicely.  Bake another 3 minutes. Spread melted chocolate and let cool completely.  

Frost with:
1/2 cup peanut butter
2/3 cup powdered sugar
1/2 cup butter
2-4 Tbs.evaporated milk 
Mix until fluffy, adding enough milk to reach good spreading consistency.  Spread on cooled bars.You can double this recipe and bake in a large cookie sheet.