Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Place the diced zucchini, red bell pepper, and red onion on the baking sheet and drizzle with avocado oil.
Season the vegetables with sea salt, black pepper, and garlic powder, then toss to coat evenly.
Roast the vegetables for 15-20 minutes until they are tender and slightly caramelized at the edges.
While the vegetables roast, whisk the whole eggs and egg whites together in a medium bowl until well combined.
Heat a large non-stick skillet over medium-low heat and pour in the egg mixture.
Cook the eggs slowly, stirring frequently with a silicone spatula to create soft, fluffy curds.
When the eggs are nearly set, fold in the roasted vegetables and the fresh baby spinach.
Continue to cook for 1 minute until the spinach is just wilted.
Transfer the scramble to a plate and top with the crumbled feta cheese before serving warm.