Wrap bars individually in plastic wrap and place in an airtight container; cover. Store at room temperature for up to 1 week.
Chocolate-Dipped Marshmallow Treats:
In a small heavy saucepan cook and stir 1 1/2 cups bittersweet or semisweet chocolate pieces and 6 ounces chocolate-flavor candy coating over low heat until melted and smooth. Cut bars as directed. Dip half of each heart into melted chocolate mixture, letting excess drip back into saucepan. Place on waxed paper. If desired, sprinkle with desired sprinkles.
Caramel-Pretzel Mallow Treats:
Carefully spread caramel-flavor ice cream topping over cereal mixture. Sprinkle with chopped pretzels.
Carefully spread creamy peanut butter over cereal mixture. Dot with strawberry or grape jelly on top of peanut butter. Using a knife or small metal spatula, swirl the jelly into the peanut butter.
Frosting 'n Sprinkle Treats:
Spread canned vanilla frosting over cereal mixture. Sprinkle with multicolored jimmies.