You should not bake Rice Krispie Treats because they are a type of no-bake cookie. Prepare the treats in a saucepan on the stove top and then cool them in a greased baking dish.
Pour 6 cups of crispy rice cereal into a large mixing bowl. Put 3 tablespoons of butter in a saucepan with 10 ounces of marshmallows. Set the stove's burner on low heat and stir constantly until the butter and marshmallows melt into a thick marshmallow sauce, then pour the marshmallow sauce over the rice cereal. Immediately mix the marshmallow sauce and cereal together and spread the mixture into the baking dish. Let the mixture cool before cutting the pan of treats into squares.