Crab cake: Mix all of the ingredients together except the vegetable oil. Add breadcrumbs, as needed, if the preparation does not bind together. Form 4 small patties. For a crispier coating, add Panko breadcrumbs on both sides. Pour the vegetable oil in a frying pan over medium heat and cook the patties for 2 minutes on each side. Set aside on paper towels.
Mayo: In a small bowl, whisk the egg yolk and Dijon mustard together while simultaneously drizzling in the oil. Add the zest, lime juice and coriander. Salt and pepper. Set aside in the refrigerator.
Assembly: Cut the base of the avocado so it can stand. Cut the avocado in half across the width. Remove the pit and gently peel the avocado. Place the avocado base on a plate, pour the mayonnaise inside the pit hole and place a crab cake on top. Add a slice of cheese, the tomatoes, salad greens and other piece of avocado. Sprinkle the top of the avocado with sesame seeds. To be eaten with utensils ;)