Mix meat, breadcrumbs, Worcestershire sauce, liquid smoke, and pepper very well. A pinch of salt can be added if desired.
Shape into 3 patties of about 1/2″ thick.
Let sit in fridge for about 15 minutes.
In a separate bowl combine sliced avocado, chopped onion, tomatoes, cilantro, and lemon juice. Mix well until all ingredients are well blended and it has a guacamole like consistency.
Preheat your Foreman Grill for at least 5 minutes with the lid closed.
Place burger patties on grill and close lid.
Grill for approximately 5 minutes for medium doneness.
After patties are done, place buns on grill but don’t close the lid. Let grill for about 1 minute.
Add avocado spread to tops of burgers and serve warm.
Add your favorite cheese if desired.