01 -
Place parchment paper in a square pan, 9 inches wide.
02 -
Heat butter in a big pan and stir in all except 1 cup of marshmallows until smooth and gooey.
03 -
Turn off the heat and pour in vanilla. Toss in the cereal and leftover marshmallows, mixing it all together.
04 -
Spread into the pan lightly using wet hands. Wait an hour to firm up before slicing.