Gather 3 tablespoons butter, 1 package marshmallows, and 6 cups crispy rice cereal
Grease a 9×13-inch pan
Melt the butter in a large pot over low heat
Add the marshmallows and stir until completely melted
Remove the pot from heat
Stir in the crispy rice cereal until evenly coated
Press the mixture into the greased pan with a buttered spatula or wax paper
Let the treats cool and set
Cut into squares and serve
