Heat olive oil in a nonstick skillet over medium heat. Add onion and bell pepper; sauté 2–3 minutes until softened.
Add mushrooms; cook 2 minutes more until tender. Stir in spinach and cook until just wilted.
In a bowl, whisk eggs with a pinch of salt and pepper. Pour into the skillet over the veggies.
Gently scramble with a spatula, pushing from edges to center, until eggs are softly set and slightly creamy (do not overcook).
Meanwhile, toast the whole-wheat bread. Top each slice with avocado slices; season lightly with salt and pepper.
Divide scrambled eggs between two plates and serve alongside avocado toast. Add optional cheese if using.
Calories: Not specified
Recipe Notes:
Swap veggies based on what you have (zucchini, tomatoes, kale).
For extra protein, add 1–2 egg whites or a side of Greek yogurt.
Make-ahead tip: Pre-chop veggies the night before to cut morning prep time.
Storage: Best eaten fresh; leftovers keep 1 day refrigerated and reheat gently on low heat.