From America's Test Kitchen Season 12: Salmon and Sole
We wanted a fuss-free, foolproof sole preparation that was suitable for a weeknight dinner yet impressive and elegant enough to serve to company. We found that rolling the fillets into compact bundles eased the transport from baking dish to plate and covering the baking dish with foil protected the delicate fish from the drying heat of the oven. To ramp up the fillets’ mild flavor, we brushed them with Dijon mustard; seasoned them with salt, pepper, fresh herbs, and lemon zest; and drizzled them with melted butter and garlic. Then we rolled them up, drizzled them with more butter, and baked them. For texture, we added a mixture of herbs, butter, and panko bread crumbs to the sole at two intervals. We removed the foil before the fish was done cooking, basted the fillets with pan juices, topped them with most of the bread-crumb mixture, and then returned them to the oven uncovered. Just before serving, we sprinkled the remaining crumbs over the fillets.
Try to purchase fillets of similar size. If using smaller fillets (about 3 ounces each), serve 2 fillets per person and reduce the baking time in step 3 to 20 minutes. We strongly advise against using frozen fish in this recipe. Freezing can undermine the texture of the fish, making it hard to roll. Fresh basil or dill can be used in place of the tarragon.