Line your 9x13 inch baking dish with parchment paper for easy cleanup and set aside.
Melt 3 tablespoons of butter in a large saucepan over low heat, stirring occasionally until just shimmering and melted. The butter should smell rich and slightly nutty.
Add the marshmallows to the melted butter and stir constantly with a sturdy spatula until completely melted and the mixture becomes shiny and gooey. You’ll hear a gentle bubbling and see the marshmallows smoothly blending in.
Remove the saucepan from heat and immediately pour in the Rice Krispies cereal. Stir quickly and gently to coat all the cereal evenly with the marshmallow mixture, creating a sticky, glossy mass.
Using a buttered spatula or wax paper, press the mixture firmly and evenly into the prepared baking dish. You want a thick layer that’s pressed flat, but avoid pressing too hard to prevent cracking.
Let the treats sit at room temperature for at least 30 minutes until they are set, firm, and slightly golden on top. This allows the marshmallow to cool and the treats to become chewy and satisfying.
Once cooled, use a sharp knife to cut into squares or rectangles, wiping the knife with a damp cloth between cuts for clean edges. The treats should be thick, chewy, and loaded with marshmallow goodness.
Enjoy your monster-sized Rice Krispie treats! They’re perfect for sharing or indulging in nostalgic, gooey goodness.
