1 1/3 pounds ground turkey breast, the average weight of 1 package  | 
                                                salt and pepper  | 
                                                6 crimini mushrooms (baby portobellos) stems removed and finely chopped  | 
                                                1/2 red bell pepper, seeded and chopped  | 
                                                1/2 yellow onion, finely chopped  | 
                                                2 cloves garlic, smashed away from skin and finely chopped  | 
                                                3 tablespoons tomato paste  | 
                                                1 tablespoon worcestershire sauce  | 
                                                1 teaspoon crushed red pepper flakes  | 
                                                1/2 cup grated parmigiano-reggiano or romano, a couple of handfuls  | 
                                                handful flat-leaf parsley, chopped  | 
                                                extra-virgin olive oil, for drizzling  | 
                                                4 large portobello mushroom caps, stems removed  | 
                                                coarse salt and black pepper  | 
                                                2 cups arugula leaves, coarsely chopped  | 
                                                1/2 pound fresh mozzarella or fresh smoked mozzarella, thinly sliced  | 
                                                sliced red onion and sliced yellow and plum tomatoes  |