They’re magically delicious!
1 stick unsalted butter, plus more for the pan
2 10-oz bags mini marshmallows, divided
1 teaspoon vanilla extract
8 cups Lucky Charms
Line a 9 x 13-in pan with parchment paper and lightly grease with softened butter. Set aside 2 cups of the marshmallows. Heat stick butter to bubbling, add half the marshmallows. Remove from heat, add the rest of the marshmallows and the vanilla. When the marshmallows are melted, add cereal and stir until well-blended but still warm and gooey. Press evenly into baking pan, bake on center rack at 300 for about 20 mins. Cool at room temperature for an hour, and cut into squares.