Decorated cupcakes can be made ahead of time. Prepare as directed, except do not top with marshmallows and graham pieces. Refrigerate up to 8 hours. Top with marshmallows and graham pieces just before serving.
If you don't have 24 jelly jars, you can fill the split cupcakes on a platter instead.
How to Easily Drizzle Melted Chocolate
Melt BAKER'S Baking Chocolate as directed on package. Use a teaspoon to drizzle chocolate back and forth over dessert in desired design. Or, spoon melted chocolate into small resealable plastic bag; press out excess air and seal bag. Cut small piece (about 1/8 inch) from one of the bottom corners of bag. Use bag to drizzle chocolate over dessert.