Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Dice the bell pepper, zucchini, red onion, and chicken sausage into uniform, bite-sized pieces.
Place the chopped vegetables and sausage on the baking sheet, then drizzle with olive oil and sprinkle with sea salt, black pepper, and garlic powder.
Toss everything to coat evenly and roast in the oven for 15 to 18 minutes until the vegetables are tender and slightly caramelized.
While the vegetables roast, whisk the whole eggs, egg whites, and plain Greek yogurt in a medium bowl until the mixture is light and well combined.
Heat a non-stick skillet over medium-low heat and pour in the egg mixture, stirring gently with a spatula to create soft, creamy curds.
Once the eggs are nearly set, fold the roasted vegetables and sausage directly into the skillet to incorporate.
Transfer the scramble to a plate and top with the freshly sliced avocado before serving.