
Make the Guacamole first. Peel and pit the avocado and add it to a large mixing bowl.
Add the remaining ingredients and mash with a fork until fairly smooth.
Adjust for salt and refrigerate until ready to use.
FOR THE BURGERS, add all of the ingredients to a large bowl. Hand mix, but do not overmix or the burgers can become mealy. If the meat mixture is too loose/wet, add a bit more breadcrumbs to firm it up slightly.
Form the burgers into 4 quarter pound patties.
Heat the oil in a large pan and add the burger patties. Sear a couple minutes on each side, then cover and cook until they are cooked through completely, about 10 minutes.
Serve on buns with bib lettuce, then top with a heaping pile of guacamole.