Melt the butter and entire bag of marshmallows in a large saucepan over medium to low heat.
Mix in your Trix and stir to coat cereal.
Pour into a large greased pan (9 x 13) and press down with a greased gloved hand or spoon.
Put in refrigerator for 20 minutes then cut into squares.
Notes
Cooking Tip** I use {powder-free} latex gloves greased with butter to touch and press down on the crispy treats. I find it to be the least messy way to make these, especially with kids.**