Reese's No Bake Peanut Butter Bars

Bahan-bahan (16 porsi)

• 1 cup salted butter, (melted)
• 2 cups graham cracker crumbs, (about 28 whole graham crackers)
• 2 cups gula bubuk
• 1 ¼ cup peanut butter, (divided)
• 1 ½ cup semi-sweet or milk chocolate chips