Preheat the oven to 200 degrees. (if making multiple omelets keep cooked omelets in the oven on a baking sheet until all are complete)
In a medium bowl, whisk together eggs, salt, and black pepper.
In a nonstick pan, heat olive oil over medium heat. Saute spinach till wilted, add in tomatoes and egg.
After egg mixture begins to set around edges, about 25 to 30 seconds, with a heat-safe spatula, carefully lift the egg from the side and tilt the skillet, so uncooked egg can reach the bottom of the pan. Repeat this process, tilting as necessary.
In a nonstick pan on medium heat brown the chicken sausage on both sides. Toast the bread.
Add feta cheese and with a spatula fold the omelet in half and portion onto the ciabatta. Serve with chicken sausage and peaches.