Americans love things that are actually other things.
For the “burger” part, I melted an ounce of dark chocolate and added a tablespoon of powdered sugar. The “cheese” is coconut that I put in a food processor with yellow food dye. You could also use fondant, or yellow frosting. I didn’t have red food dye, but if you wanted some red frosting “ketchup”, that would look swell too.
The recipe for the macarons themselves are from David Leibowitz. Just omit the cocoa for the white cookie “buns”, and I’ve started using 3 egg whites instead of the two he recommends. It gives them a better gloss.