Preheat your oven to 400°F (200°C).
Chop the bell pepper, zucchini, and red onion into bite-sized pieces and mince the garlic.
On a large rimmed baking sheet, toss the chopped vegetables and garlic with olive oil, sea salt, black pepper, and dried oregano until evenly coated.
Roast the vegetables in the oven for 15-20 minutes, or until they are tender and just beginning to brown at the edges.
Transfer the roasted vegetables into a medium-sized oven-safe skillet or a deep baking dish, spreading them out into an even layer.
Pour the liquid egg whites over the roasted vegetables.
Carefully crack the three whole eggs on top of the mixture, spacing them out evenly.
Place the dish back into the oven and bake for 8-12 minutes, or until the egg whites are fully set and the whole egg yolks have reached your desired level of firmness.
Remove from the oven and serve immediately while hot.