Portobello Mushrooms Stuffed with Chicken

Name: Portobello Mushrooms Stuffed with Chicken
Ingredients: 1 medium head garlic; 3 tablespoons olive oil; 2 large Vidalia onions; 6 large portobello mushroom caps, stems removed (save stems); 1/2 pound crimini mushrooms; 1 1/2 pounds boneless, skinless chicken breasts cut into 1/4-strips; 1 tablespoons all-purpose flour; 1 teaspoon salt and freshly ground black pepper; 1 teaspoon red pepper flakes to taste (optional); 1/2 cup dry white wine; 1 tablespoon butter; 1 teaspoon fresh herbs, shredded (such as basil and Italian parsley) to taste; 2 each, whole green, yellow, and red bell peppers; stems and seeds removed, cut in strips; 1/4 cup shredded, aged Parmesan cheese; Thinly sliced chunks of very dry, aged Parmesan cheese, for top and presentation; Basil sprigs, for garnish