Place the chicken and turkey breasts between two sheets of parchment paper and pound them to an even half-inch thickness.
In a shallow bowl, whisk the egg until smooth.
In a separate small dish, combine the sea salt, black pepper, garlic powder, and dried oregano.
Season both sides of the meat cutlets with the spice mixture, then dip each piece into the whisked egg to coat thoroughly.
Heat the olive oil in a large skillet over medium-high heat.
Carefully place the cutlets in the skillet and sear for 4-5 minutes per side until the exterior is crisp and the internal temperature reaches 165°F.
Remove the meat from the pan and let it rest on a plate.
In the same skillet, add the cherry tomatoes and sauté for 2 minutes until they begin to soften.
Add the baby spinach to the pan and toss for 1 minute until just wilted.
Serve the cutlets immediately with the warm vegetable sauté on the side.