Season chicken with 1/4 teaspoon each salt and pepper. Heat 2 tablespoons oil in large high sided skillet set over medium heat; cook chicken in batches for 8 to 10 minutes or until browned all over. Transfer chicken to plate.
Heat 1 tablespoon oil in skillet set over medium heat; cook yellow onion, 3 teaspoons garlic, thyme 1/2 teaspoon oregano for 2 to 3 minutes or until softened.
Stir in soup and 1/2 cup water; bring to boil. Reduce heat to medium low. Stir in Dijon, lemon zest and lemon juice. Return chicken to skillet; cover and cook for 20 to 25 minutes or until chicken is cooked through.
Whisk together remaining 3 tablespoons oil, vinegar, remaining 1 teaspoon garlic, remaining 1/2 teaspoon oregano, and remaining 1/4 teaspoon each salt and pepper. Add green pepper, tomato, cucumber, olives and red onion. Toss well. Sprinkle feta cheese over top.
This nutritional information refers to each serving of the entire recipe and not just the products used as ingredients.