Heat oil in saucepan, add onion, and sauté over medium heat about 5 minutes. Add mushrooms and sauté about 3 minutes. Add drained Grano and sauté lightly. Add stock, sun-dried tomatoes, salt, pepper, cayenne, and dried basil, if using, and bring to a boil. Cover and cook 10 minutes over low heat. Add corn and peas, stir lightly, and cook covered for 5 minutes or until tender and liquid is absorbed. Stir in chicken and let stand to heat through. Add basil. Taste and adjust seasoning.