Step 1

Grease a 13x9 inch pan with butter and set aside.

Step 2

Place a medium heavy-bottomed pot or Dutch oven over medium-low heat. Add the butter and marshmallows.

Step 3

Stir constantly until the marshmallows have melted completely.

Step 4

Add the Cheerios and mix in gently with a wooden spoon until coated evenly.

Step 5

Turn the mixture into the prepared pan. Using a spatula, press down the surface gently to flatten without crushing the Cheerios.

Step 6

Allow to cool for 10 to 15 minutes before cutting and serving.