4 (8 by 10-inch) pieces parchment paper 4 (12-inch) pieces kitchen string
In an ovenproof non-glass baking dish (11 by 8-inch), combine the coconut milk, stock, fish sauce, lime juice, ginger, serrano, garlic, cilantro, and Thai basil. Add the fish, turn to coat, cover, and refrigerate for 30 minutes to 1 hour.
Preheat the oven to 325 degrees F.
Remove the fish from the marinade and reserve. Add the vegetables to a small ovenproof dish and cover with the marinade. Cover tightly with aluminum foil and place in the oven for 15 to 20 minutes.
Once the vegetables are cooked, drain the marinade/cooking liquid into a small saucepot and place over medium-low heat to reduce.
Pat the fish dry and strain as much liquid from the vegetables without damaging them. In the center of a piece of parchment, place 1/4 of the vegetables, top with 1 portion fish, and 1 slice fresh lime and fold the parchment around the fish and vegetables like a package. Secure with the kitchen string and place on a baking sheet. Repeat with remaining ingredients. Bake for 15 to 20 minutes.
Remove the packets to individual serving plates, cut open to reveal, and garnish with a sprinkle of fresh cilantro and a wedge of lime.