This is burgers my way;
1. equal amounts of 90% ground beef and pork sausage, ground pork will work.
2. sweet onion diced, the mount you like, me lots and lots.
3. your favorite cheese shredded, in the amount you think you need.
4. one tablespoon of chili powder (for 1 lb of ground beef and 1 lb pork sausage)
5. 1 egg (for 1 lb ground beef and 1 lb pork sausage)
Mix everything except the beef together, when fully mixed add the beef, allow to sit in a refrigerator for 4 hours up to overnight for the flavors to marry. Weigh out a third pound and form into burger, I like smoking them but they work well in a gas grill or charcoal grill.
Toast buns and load them up, use the condiments of your choice, the cheese is melted inside the burger so you don't need to worry about that.
I think I posted this before but am too lazy to look.
Rodney