1/2 c. soft butter
1/2 c. brown sugar, packed
1/2 c. peanut butter
1/2 tsp. vanilla extract
1 egg
1/2 tsp. baking soda
1/4 tsp. salt
1 1/2 c. all-purpose flour

Cream butter with sugar and peanut butter. Add vanilla and egg, beating until fluffy. Stir in baking soda and salt. Blend in flour. Mix until a stiff dough forms. Shape into walnut-sized balls. Place on lightly greased cookie sheets. Press with fork to flatten. Bake at 375 degrees for 10 to 12 minutes or until lightly browned.