Spray a small skillet with non-stick cooking spray. Add the spinach and cook over medium heat until spinach is wilted. Place in a small bowl and set aside.
Mash the avocado with a fork and spread evenly on piece of toast. Top the avocado toast with spinach, scrambled eggs, and tomato slices. Season with salt and pepper, to taste. You can also add everything bagel seasoning. Serve immediately.
Note-to make this gluten-free, use gluten-free bread.