Makes 2 servings, or 4 muffin cups

1 tablespoon unsalted butter (plus more for pan)

1 1/4 cups mini marshmallows

1 1/2 cups rice crispies

Begin by greasing your pan of choice with the extra butter.
In a heavy saucepan, melt the butter and marshmallows together. When smooth, stir in the rice crispies. Immediately scrape the mixture into the pan. Smooth the surface with a non-stick spatula. Let cool completely, then serve.