Preheat your oven to 400°F (200°C).
In a small oven-safe baking dish or cast-iron skillet, toss the cherry tomatoes with olive oil, sea salt, and black pepper.
Roast the tomatoes for 10 minutes until they begin to soften and the skins start to burst.
While the tomatoes roast, whisk together the Greek yogurt, liquid egg whites, and garlic powder in a medium bowl until the mixture is completely smooth.
Remove the baking dish from the oven and stir in the fresh baby spinach, allowing the residual heat to wilt the leaves slightly.
Pour the yogurt and egg white mixture over the roasted tomatoes and spinach, spreading it into an even layer.
Carefully crack the 3 whole eggs onto the surface of the mixture, spacing them out evenly.
Sprinkle the crumbled feta cheese over the top of the dish.
Return the dish to the oven and bake for 12-15 minutes, or until the whites are fully set but the yolks remain jammy and golden.
Remove from the oven and garnish with freshly chopped basil before serving warm.