Baked Cod and Fennel in a Package

Name: Baked Cod and Fennel in a Package
Ingredients: 1 bulb fennel, cored and thinly sliced (mandilone works great); 1/2 red onion, thinly sliced; 4 large cloves garlic, chopped; 4 ounces mini roma tomatoes (or grape tomatoes); 2 pounds cod fillets, cut into 4 portions (ask for thicker pieces, maybe center); 1 lemon zested and juiced; 4 tablespoons white wine (pino grigio); 1/4 cup flat-leaf parsley, a generous handful, chopped; Extra-virgin olive oil, for generous drizzling; 1 lemon wedge garnish