No Bake Chocolate Oat Bars

1 c. butter
1/2 c. firmly packed brown sugar
1 tsp. vanilla
3 c. uncooked oats
1 c. chocolate chips
1/2 c. peanut butter

Grease 9 inch square baking pan (double recipe for 9 x 13 inch pan). Melt butter in large saucepan over medium heat. Add brown sugar and vanilla; mix well. Stir in oats. Cook over low heat 2 to 3 minutes or until ingredients are well blended. Press half of mixture into pan. Use back of large spoon to spread mixture evenly. Meanwhile, melt chocolate chips in small heavy saucepan over low heat, stirring occasionally. Stir in peanut butter. Pour chocolate mixture over oat mixture in pan; spread evenly with knife or back of spoon. Crumble remaining oat mixture over chocolate layer, pressing gently. Cover and refrigerate 2 to 3 hours or overnight. Bring to room temperature before cutting into bars.