Line an 8x8-inch baking sheet with foil or parchment paper.
In a large bowl mix the ½ cup melted salted butter, ½ cup graham cracker crumbs, 1 cup powdered sugar, and ¾ cup creamy peanut butter. Stir in the ½ cup rice krispies cereal then press the mixture into the pan.
In a small microwave-safe bowl, add the 1 cup dark or milk chocolate chips and 2 tablespoons coconut oil, and microwave in bursts of 15 seconds, stirring in between bursts.
Pour the melted chocolate over the peanut butter layer and let it completely firm up before cutting into bars.