Start by melting 1/2 a tablespoon of butter in a microwave safe bowl.

Then add four large marshmallows and microwave again for about twenty more seconds.

The marshmallows will start puffing up, so keep an eye on them so they don't come over the edge of the bowl.

Once you remove the bowl from the microwave, they will deflate again.

Stir the melted butter and marshmallows together until smooth.

Mix in 1 cup of Rice Krispie cereal and stir until well blended.