Best Instant Pot Chicken Cacciatore

Name: Best Instant Pot Chicken Cacciatore
Prep time: 30 min
Cook time: 35 min
Total time: 1 h 5 min
Cuisine: European, Italian, Mediterranean
Ingredients: 1 pound skinless, boneless chicken thighs; 2 small skinless, boneless chicken breasts, halved lengthwise; 1 tablespoon sea salt; 1 tablespoon fresh ground black pepper; 0.25 tablespoon cornstarch; 3 tablespoons extra-virgin olive oil, divided; 3 stalks celery, chopped; 1 small onion, chopped; 4 cloves garlic, minced; 1 (8 ounce) package sliced fresh mushrooms; 1 green bell pepper, diced; 1 red bell pepper, diced; 2 large jarred roasted red bell peppers, chopped; 0.75 cup dry Cabernet Sauvignon; 3 tablespoons tomato paste; 2 teaspoons garlic powder; 2 teaspoons onion powder; 2 teaspoons chicken bouillon granules; 2 teaspoons Italian seasoning; 1.5 teaspoons red pepper flakes, or to taste