Preheat your oven to 400°F and line a small baking sheet with parchment paper.
Toss the diced bell pepper, zucchini, and red onion with olive oil, sea salt, and black pepper on the prepared baking sheet.
Roast the vegetables for 15 minutes until they are tender and slightly caramelized around the edges.
In a medium bowl, whisk together the whole eggs and egg whites until well combined and frothy.
Heat a non-stick skillet over medium heat and add the sliced chicken sausage, browning for 2-3 minutes per side.
Add the roasted vegetables to the skillet with the sausage, then pour in the egg mixture.
Gently stir the eggs with a spatula until they are just set and fluffy.
Remove from heat and top with crumbled feta cheese and freshly chopped chives before serving.