Step 1

Line a 9x9 or 8x8 baking pan with parchment paper leaving an overhang on 2 sides or alternately spray with cooking spray.

Step 2

Remove one cup of marshmallows from the bag and set aside. In a large saucepan, melt the butter, all but 1 cup of the marshmallows and the peanut butter over medium heat. Stir constantly until it's fully melted and combined.

Step 3

Remove the saucepan from the heat and stir in the vanilla. Quickly stir in the rice krispies until combined. Once combined, stir in the reserved cvup of mini marshmallows.

Step 4

Pour the mixture into the prepared pan and smooth the top with a spatula or your hands until it's even. Don't press too hard! If it's too sticky, spray the spatula or your hands with cooking spray.

Step 5

Melt the chocolate chips in a microwave safe bowl in 30 second increments, stirring after each time until melted. Stir in the vegetable oil.

Step 6

Pour in melted chocolate over teh rice krispie treats and smooth the top. Let them sit for at least 30 minutes to allow the chocolate to harden.

Step 7

When you are ready to serve them, lift the whole block of rice krispie treats out of the pan using the parchment overhang. Slice them with a large knife.