Line a 9×13 inch baking pan with parchment paper. Lightly grease parchment. Set aside.
Melt butter over medium heat in a large pot. Once melted, add marshmallows. Stir mixture until marshmallows are all melted.
Remove from heat, then immediately stir in the vanilla extract and salt. Finally, fold in cereal and chocolate chips. Stir until all cereal is coated with marshmallow mixture.
Transfer mixture to prepared pan. Using a greased rubber spatula, gently spread mixture to fit pan. Do not pack it down, just lightly press mixture down so it is secure in pan. If desired, garnish with more chocolate chips for an extra chocolate topping.
Allow treats to set for at least 1 hour at room temperature.
Lift treats as a whole out of the pan using parchment paper. Cut into squares.