Crack your whole eggs into a bowl and add the egg whites along with the garlic powder, onion powder, a pinch of salt, and a few grinds of black pepper. Whisk these together until well combined. Pour the egg mixture into your skillet with the sausage and vegetables.
Reduce the heat to medium and cook, stirring gently but frequently, until the eggs are scrambled to your preference. I like mine just set but still slightly creamy, which takes about 3-4 minutes. If you prefer firmer eggs, cook a bit longer. The residual heat in the pan will continue cooking them slightly even after you remove it from the heat, so aim for just slightly underdone and you'll hit the mark perfectly.
This is also your moment to taste and adjust seasoning. If you want more salt, pepper, or garlic, add it now before you move to assembly.