In a small and flat oven-safe dish, stack the chocolate bars on the bottom, one on top of the other. You may need to break up the chocolate to conform to the shape of the dish.
Bake at 350°F for 8-10 minutes or until the chocolate is melted through and easily spreadable.
Spread the chocolate into any open spots with a spatula. Cut your jumbo marshmallows in half and evenly place them over top of the melted chocolate.
Turn the oven to broil, and place the dish back in the oven. Watch it closely for 2-3 minutes or until marshmallows are fully toasted.
Remove from the oven and immediately serve with graham crackers or dippers of choice (e.g. nilla wafers, cookies, etc.)