In a nonstick skillet over medium heat, melt a little butter.
Add chopped onion and cook until softened, about 3 minutes. Stir in the tomato and spinach, and sauté until the spinach wilts.
Stir in the tomato and spinach, and sauté until the spinach wilts.
Crack the eggs directly into the skillet and stir gently with a spatula to scramble and combine with the veggies. Cook until the eggs are just set.
Sprinkle shredded cheese over the eggs. Let it melt slightly, then fold the eggs over the cheese.
Season with a pinch of salt and a shake of everything bagel seasoning.
Toast your bagel or English muffin. Pile the egg scramble onto the bottom half, top with the other half, and enjoy warm!