1In 12-inch nonstick skillet, heat oil over medium heat. Sprinkle chicken with garlic, oregano, seasoned salt and pepper. Add chicken to skillet; cook 15 to 20 minutes, turning once, until juice of chicken is clear when center of thickest part is cut (at least 165°F).
2Stir wine into skillet. Top chicken with tomato slices. Cover; cook 2 to 3 minutes or until tomatoes are thoroughly heated.
3Add spinach. Cover; cook 2 to 3 minutes longer or until spinach is wilted.