01 -
Put parchment paper in a 9-inch square pan and give it a quick spray with oil.
02 -
Throw the peanut butter, butterscotch chips, and butter into a saucepan. Use medium-low heat and stir all the time until the chips are melted and it's smooth.
03 -
Pour in the vanilla extract and salt, then stir until blended well.
04 -
Scoop out and keep 1 cup of marshmallows on the side. Gently add the rest to the warm but not too hot mixture, folding to combine without melting everything.
05 -
Firmly pack the mixture into the pan you prepped earlier. Sprinkle the saved marshmallows on top and lightly press them in so they stick.
06 -
Chill it in the fridge until firm, about an hour. Once it's set, slice into squares and enjoy.