01 -
Line a 9x13-inch pan with parchment paper and lightly butter the parchment.
02 -
In a large pot over low heat, melt the butter with the peanut butter. Add the marshmallows and stir until mostly smooth, 3-4 minutes.
03 -
Remove the pot from the heat. Add the chocolate chips, vanilla, and salt, then stir until the chocolate melts and the mixture looks glossy.
04 -
Add the crispy rice cereal and fold gently until coated. Work quickly while the mixture is still warm.
05 -
Transfer to the prepared pan. Press lightly into an even layer without compacting the cereal. Cool at room temperature for 20-25 minutes, or chill for 10 minutes.
06 -
Lift the slab from the pan and cut into 20 squares. Place powdered sugar in a large bag or bowl and gently coat the squares before serving.