Season chicken with 1/2 tsp. salt and pepper to taste.
Heat 1/2-1 Tbsp. oil in large skillet over medium heat, then add chicken. Brown for 6 minutes on each side or until medium brown.
Remove chicken and set aside on a plate.
Add another 1/2-1 Tbsp. oil to pan. Add onion and garlic. Saute for 1-2 minutes or until softened.
Layer on pieces of sliced zucchini. Cook until slightly golden brown.
Push zucchini aside and add sun-dried tomatoes and bell peppers. Stir gently.
Transfer chicken back into the pan and add chicken stock. Turn heat to medium low and cover until chicken is cooked through and sauce is slightly reduced (~ 7-9 minutes).
Add oregano, cilantro, basil and parsley. Allow to simmer for 2 minutes, uncovered.
Remove from heat and garnish if desired. Add salt and pepper to taste.