Preheat oven to 375°F (190°C) and lightly grease a small baking dish.
Heat olive oil in a skillet over medium heat, then add the ground turkey, breaking it apart until browned and cooked through.
Stir in the diced onions and bell peppers, sautéing for 3-4 minutes until the vegetables are softened and fragrant.
Add the chopped spinach to the skillet and stir until just wilted, then remove the pan from heat.
In a medium bowl, whisk together the egg whites, whole egg, sea salt, black pepper, garlic powder, and oregano until well combined.
Spread the turkey and vegetable mixture evenly across the bottom of the prepared baking dish.
Pour the egg mixture over the turkey and vegetables, ensuring everything is evenly submerged.
Bake for 25-30 minutes, or until the center is set and the edges are lightly browned and pull away from the sides.
Let the bake cool for 5 minutes before slicing into portions for meal prep.