Mix all “patty” ingredients together, form into six equal balls and fridge 4 hours – overnight, covered. Press into rounds slightly larger that the buns and freeze 3-4 hours between maxed paper.
Make simple guacamole and keep chilled.
Start coals or gas grill and heat to high, lightly grill buns (cut side only) and remove, then throw a small handful of oak chips on the fire, if you have them.
Cook bacon in pan, drain on paper towels and wrap in foil. These can be set on the back of the grill to re-heat just before using.
When grill is hot, place frozen patties evenly on surface and close the lid. Check occasionally for flare-up (these are high fat burgers) and perhaps have a spray bottle of water handy to keep the flames down. Cook 3-5 minutes.
Meanwhile, prep buns with mayo and guacamole
Flip burgers and place 1 slice of cheese on top of each. Cover and cook 2 minutes. Check to see if cheese has melted, if so, place three half-strips of bacon on each patty and remove from grill.
Spread 1 Tbs of mayo on each bottom bun, and 2 Tbs of guacamole on each top bun.
Place bacon cheese-burger patty between them, add sliced onions and lettuce, and serve immediately. (Best if patties are taken directly from grill and placed on waiting buns.)