Quick Chicken Stew

Name: Quick Chicken Stew
Prep time: 20 min
Cook time: 1 h
Total time: 1 h 20 min
Cuisine: European
Ingredients: 1 tbsp olive oil; 1 ½ cup onions, diced; 1 cup celery, sliced (include some leaves); 6 potatoes, medium, peel on; 3 cups carrots, peeled and sliced; 2.2 lb boneless, skinless chicken breasts; 4 cups low-sodium chicken broth; 1 tsp thyme, dried; ½ tsp oregano, dried; ½ tsp black pepper; 2 bay leaves; 5 tbsp cornstarch; ¼ cup cold water; ¼ tsp salt; ½ cup parsley, fresh, chopped, for garnish