Vanilla bean paste and fancy sprinkles will make crispy rice bars a party favorite.
Mix It Up: Line a 9-by-13-inch pan with foil and spray with cooking spray. In a large pot, melt the butter over high heat. Stir vanilla bean paste or pure vanilla extract into the melted butter. Add the bag of marshmallows and 1/2 tsp. salt and, using a silicone spatula, stir until smooth. Remove from heat. Add the cereal and mix until evenly coated. Mix in the remaining 2 cups marshmallows and 1 cup fancy sprinkles, stirring just until incorporated but not melted.
Top It Off: Transfer the cereal to the prepared pan. Spray a clean spatula with cooking spray; pat the cereal into an even layer. Top the warm treats with 1/4 cup fancy sprinkles. Let cool for 2 hours. Cut into squares.