Preheat oven to 375 degrees F
In a small bowl, mix white miso, mirin, ginger and lime juice until well-combined. Generously coat flesh of fish filets and let stand at room temperature for ~30 minutes while you chop and trim the vegetables. Lightly season vegetables with a dash of salt and pepper.
Place three 18-inch square pieces of parchment paper on a flat surface. Fold each piece in half to create a crease in the center. Place 6 stalks of asparagus lengthwise next to the crease and top with one third of the sliced red pepper and 4-5 slices of eggplant.
Gently place one fish filet on top of the vegetables and top with sliced green onion and sesame seeds. Fold the parchment paper over the fish. Starting at one end and repeating on all open sides, making small, tight, overlapping folds in the parchment paper to create a sealed packet around the fish (refer to picture above).
Repeat with remaining parchment and filets. Place packets on a baking sheet and bake for ~20 minutes, depending on thickness of filet.
Transfer packet to a plate and carefully slice open with a knife. You can choose to remove contents or simply eat right out of the bag!