01 -
Line a 9x13-inch pan with parchment paper, leaving overhang on two sides. Lightly butter or spray the parchment and the sides of the pan.
02 -
Melt the butter in a large pot over low heat. Add the mini marshmallows and salt, stirring until just melted and smooth, 3-4 minutes.
03 -
Remove the pot from the heat. Stir in the vanilla extract so it blends into the warm marshmallow mixture.
04 -
Add the Franken Berry cereal and fold quickly with a greased spatula until every piece is coated. Work gently so the cereal stays crisp.
05 -
Transfer the mixture to the prepared pan. Press into an even layer with buttered hands or a greased spatula, using light pressure only.
06 -
Add melted white chocolate, candy eyes, or sprinkles if using. Let the bars set at room temperature for 20-30 minutes.
07 -
Lift the slab out with the parchment. Cut into 12 squares with a lightly buttered knife and serve the same day for the best texture.