Prepare the jello per box instructions and pour into a large glass baking dish to create a 1" thick layer. To make the jello stiffer and more moldable, add a few pinches of gelatin powder before pouring into the dish.
After the jello has set, use the cookie cutter to punch out the coins.
If the cookie cutter starts sticking, hit it with some oil and then wipe away any excess oil.
Notes
This is the perfect excuse to dust off Grandma's formal china. Your guests will love the formality of the serving ware contrasted with this super silly food!