From "Jane Brody's Good Seafood Book", 1994. Use any thin fillet, like sole, catfish, tilapia, bluefish, or mackerel. Rolls can be made ahead through step 4, then baked 20 minutes before serving time.
Select 4 large, whole leaves of chard. Cut off the stems and, with a sharp knife, shave off any thick part of the center ribs. Set the prepared leaves aside, then chop the remaining chard and set it aside.
Briefly heat the olive oil in a large nonstick skillet. Add the scallions and saute them one minute. Add the garlic, saute for 30 seconds, add the reserved chopped chard, salt, red pepper flakes, and ground pepper, saute about 5 minutes or until the chard is just cooked and reduced in volume.
Place the fillets on a work surface. Spread each fillet with 1/4 of the cooked vegetable mixture. Roll up the fillets, starting with the tail (narrower) end. The wrap one reserved chard leaf around each roll.
Spray a baking dish with the vegetable oil. Place the wrapped fish rolls in the dish and spray the tops of the rolls with vegetable oil.
Place the baking dish in the hot oven and bake the fish rolls for 15 minutes, or 20 minutes if the fillets are on the thick side.