Prep your ingredients: Crack and separate eggs, or pour liquid egg whites into a measuring cup. Dice the onion and bell pepper, slice mushrooms, and chop the spinach and herbs.
Heat the pan: Place a nonstick skillet over medium heat and add the oil.
Let it warm for about 30 seconds.
Sauté the aromatics: Add onion and bell pepper with a pinch of salt. Cook 2–3 minutes until slightly softened.
Add mushrooms and garlic: Stir in mushrooms and cook until they release moisture and start to brown, about 3 minutes. Add garlic and cook 30 seconds, stirring.
Wilt the greens: Toss in the spinach and cook just until wilted.
Sprinkle in smoked paprika or chili powder if using.
Pour in the egg whites: Reduce heat to medium-low. Pour egg whites evenly over the vegetables. Let them sit undisturbed for 15–20 seconds to start setting.
Scramble gently: Using a spatula, push the set edges toward the center, letting the uncooked egg flow to the sides.
Repeat until soft curds form and most of the liquid is set, 2–3 minutes.
Season and finish: Add salt and pepper to taste. If using cheese, sprinkle it over the scramble and cook just until melted. Remove from heat while eggs are still slightly glossy; they’ll finish cooking off the heat.
Top and serve: Add fresh herbs, avocado slices, hot sauce, or salsa.
Serve immediately with whole-grain toast or a side of berries.