Slice avocados in half, length-wise. Remove seed. Peel away the skin from the avocado halves. For each avocado, choose the prettier, rounder half. Lay the selected halves face down and then sprinkle with white sesame seeds (about 1/8 tsp each). Gently press the seeds into the surface of the avocado flesh so that they remain in place.

With your ground meat, form four quarter pound balls. Season with salt and pepper. Place onto hot grill (you can also cook in a pan on a stove) and press down gently so that the balls form patties. Cook each side a few minutes until burgers are close to your desired doneness. Add a cheese slice on top of each patty and cover the grill until burgers are done and cheese is melted.

To assemble your burgers, place each of avocado halves without sesame seeds onto a lettuce leaf. If needed, you can slice a little off the bottom of the avocados so that the avocado half has a flat surface to stand on. You can also maneuver and fold the lettuce leaves so that they help form a stable base for the avocado halves. Add 2 pieces of baby spinach, 1 slice of tomato, burger patty, 2 more pieces of spinach, any condiments you desire, and then top with an avocado half (one that has the sesame seeds). You do need to be careful as you stack the burger and place items in a way so that the weight is evenly distributed. Serve burgers while still warm.