-
Spray a 8x12 inch baking dish with cooking spray and set aside.
-
Melt butter in a large pot over medium-low heat.
-
Reserve 1 1/2 cups marshmallows and pour the remaining marshmallows into melted butter.
-
Stir constantly until marshmallows are almost melted then stir in vanilla extract.
-
Stir in crispy rice cereal and remaining marshmallows and gently stir until coated with melted marshmallow mixture.
-
Pour mixture into prepare baking dish.
-
Spray hands with cooking spray and press mixture evenly into baking dish.
-
Cool completely before cutting into squares.