Reeses Peanut Butter No Bake Bars

INGREDIENTS :
1 cup butter (melted)
2 cups graham cracker crumbs
1/4 cup brown sugar
1 3/4 cup powdered sugar
1 cup peanut butter
1/2 tsp. vanilla
1 (11 oz) bag milk chocolate chips

INSTRUCTIONS :
1. Combine all ingredients, except the chocolate chips in a medium sized bowl. Stir until the mixture is smooth and creamy.
2. Pour peanut butter mixture into a 9 x 13 pan.
3. Melt chocolate chips in the microwave (at 50% power) for 1-2 minutes. Stir chocolate and pour over the peanut butter mixture. Spread chocolate over mixture with a spatula.
4. Put bars in fridge for one hour to set. Cut while bars once cooled.