Melt the butter in a large pot.
Add the marshmallows.
Stir the butter and marshmallows until totally melted and bubbly.
Add the Rice Krispies and stir until soft and gooey.
Pour into greased pan or spray foil and pour out on the foil.
Find:
https://www.thefoodnanny.com/blogs/recipes/lizi-s-famous-rice-krispie-treats