Hi I made these cookies and they were a hit especially withe kids.
The buns are vanilla waffers. The patty is Keebler grasshopper cookie. Color frosting yellow(mustard) and red(ketchup). Spread the yellow frosting on one side of the vanilla wafer, add the grasshopper cookie put red frosting on the other vanilla waffer and place on top of the grasshopper cookie. Like a hamburger. Color some coconut green and roll the hamburger in the coconut. It appears like lettuce.

Good Luck!