Start by cutting the chicken breasts in half lengthwise to create thinner cutlets. Season each side generously with salt, pepper, oregano, and garlic powder. This step ensures every bite is packed with flavor.
Heat olive oil in a skillet over medium-high heat. Sear the chicken for 5-6 minutes per side until golden brown and cooked through. Transfer to a plate to rest while you make the sauce.
Reduce heat to medium and add minced garlic, white wine (or broth), halved tomatoes, olives, and capers to the skillet. Let the tomatoes soften slightly, releasing their juices, and form a light, flavorful sauce.
Stir in the spinach and crumbled feta. Return the chicken to the skillet and spoon some sauce over the top. Warm everything together for a few minutes until the spinach wilts and the flavors meld. Adjust seasoning with extra salt and pepper if needed.