Aromatic striped bass topped with butter, scallions, and peanuts, and served with a lime-chile dipping sauce is a delicious study in minimalism.
Preheat oven to 350 degrees. Make 3 diagonal 2-inch-long cuts on each side of fish. Rub cavity of each fish with oil; season with salt and pepper. Rub exterior and cuts of each fish with oil; season with salt and pepper. Stuff each cavity with half of the onion and ginger. Transfer fish to a 16-by-12-inch baking dish. Bake until flesh is opaque and no longer pink near spine, about 40 minutes.
Meanwhile, place sweet potatoes in a bamboo or metal steamer basket; place over boiling water in a wide saucepan or wok. Cover; steam until just tender, about 25 minutes. Transfer to a work surface; let cool slightly. Cut lengthwise into 3-inch-long sticks, about 1/3 inch thick. Set aside.
Bring a large pot of water to a boil. Add noodles; cook according to package instructions. Drain, and rinse under cold water. Cut into 2-inch lengths. Set aside.
Melt butter in a medium skillet over medium heat. Add scallions; cook until bright green, about 1 minute. Spoon over baked fish. Sprinkle with peanuts.
To assemble each wrap, soak a wrapper in a bowl of warm water until softened, about 30 seconds. Lay flat on a plate. Top with lettuce, noodles, sweet potato sticks, fish with stuffing and toppings, cilantro, and mint. Fold ends in and roll tightly to enclose filling. Serve with dipping sauce.
Use the variety of fine rice vermicelli that is packaged in coiled nests.