Cook the Angel Bay Gourmet Gluten Free Beef Patties according to instructions on the packet.
Stir the mayonnaise and the gherkin relish together, if using. Slice avocado and onion. Cut the burger buns in half and toast or grill.
Spread the bottom halves of the buns with half of the mayonnaise mixture. Top with salad greens, coleslaw, burger patty, cheese, red onion and avocado. Spread the remaining mayonnaise on the top halves of the bun and sandwich the burger together.