PREHEAT oven to 350° F.
CRUMBLE dough into medium bowl. Add flour; mix until combined.
SPRINKLE work surface lightly with flour. Roll out dough to 1/4-inch thickness, using additional flour as needed to prevent sticking. Cut out hearts with the larger heart cutter. Transfer to ungreased baking sheets, placing about 2 inches apart. With smaller cutter, cut out heart in center of each big heart. Keep these smaller hearts; these hearts will be baked as well. Remaining scraps of dough can be rolled out again to make more hearts.
BAKE larger hearts for 10 to 11 minutes and smaller hearts for 9 to 10 minutes or until golden brown. Cool on baking sheets for 2 minutes; remove to wire racks to cool completely. Line one baking sheet with wax paper. Place large hearts with no center on prepared baking sheet.
SPOON small amount of melted chocolate in center of large hearts. Tap baking sheet to spread chocolate. Use remaining chocolate to lightly frost smaller hearts. Decorate melted chocolate with sprinkles. Refrigerate for 10 minutes to set chocolate. Store in single layer in airtight containers at room temperature.