Rinse and chop the tomato, bell pepper, and yellow onion into uniform 0. 25-inch pieces; set aside in a small bowl.

In a separate small mixing bowl, beat the 3. 0 large (150g) eggs with the sea salt and black pepper until the yolks and whites are well blended and slightly frothy.

Set a 10-inch non-stick skillet over medium heat and add the 1.0 tsp (5g) of coconut oil, swirling to coat the bottom of the pan thoroughly.

Pour exactly half of the egg mixture into the heated pan and tilt the skillet in a circular motion to ensure the eggs cover the entire bottom surface.

When the eggs are almost set but still slightly moist on top, add half of the diced turkey, spinach, and vegetable mixture to one side of the omelet.

Fold the empty side of the egg over the top of the filling using a heat-resistant spatula and continue to cook for an additional 2.0 minutes until the cheese (if adding) or vegetables are heated through.

Repeat the process with the remaining ingredients for the second serving and serve the dish warm immediately.

Sauté for Flavor Depth: For an even better texture, quickly sauté your diced onions and peppers in the skillet for 2-3 minutes before adding them to the egg. This removes excess moisture and prevents a "watery" omelet.

Don't Over-Whisk: Use a fork to beat the eggs until the yolks and whites are just combined. If you over-whisk and create too many bubbles, the omelet can become tough and rubbery rather than tender.