Though there may be creative ways to serve the burger, nothing beats the classic sandwich: a round bun with mayonnaise, ketchup and mustard, the tomato and pickle slices as well as chips on the side to liven things up. There’s no reason vegetarians cannot enjoy this staple of Western cuisine in King’s Vegan Shiitake Burger! By the way, the bacon burger is right around the corner with King’s Vegan Bacon.