Place the meat in a large mixing bowl or casserole dish. In a smaller bowl, combine the egg, salt, soy, Worcestershire, steak, and teriyaki sauces. Stir well and add to the meat bowl. With clean hands, incorporate the liquids into the meat.
Form the meat into burger patties about the size of your palm, just under half a pound per person.
Get the grill (or grill pan) nice and hot. If on an outdoor grill, cook the patties with the top on for about 5 minutes (until the bottom becomes seared and the top begins to gray) and then flip. Replace the top and cook for about 4 more minutes. When close to finished, add cheese and briefly toast the buns. Once cheese is melted, serve immediately.
Recommended serving technique as follows: take a few avocado slices, mash them up with a fork (so that they don’t make the bun slippery) and then put them on top of the burger. Add mayo and mustard on the top half of the bun, and create a generous kiddie pool of ketchup on your plate for dipping.