1Heat oven to 350°F. Place mini paper baking cup in each of 24 mini muffin cups.
2Make cake mix as directed on box, using water, oil and eggs. Fill muffin cups two-thirds full. (Cover and refrigerate remaining batter until ready to bake; cool pan 15 minutes before reusing.) Cut each piece of chocolate candy in half; press 1 half into batter in each muffin cup.
3Bake 12 to 15 minutes or until surface of cupcakes appears dry. Cool 5 minutes; remove cupcakes from pans to cooling racks. Cool completely. Repeat with remaining batter and chocolate pieces to make an additional 48 mini cupcakes.
4In medium bowl, mix frosting and marshmallow crème. Frost cupcakes. Place graham crackers in resealable food-storage plastic bag; seal bag and crush with rolling pin. Sprinkle crushed graham crackers over cupcakes.