A super easy and fabulously delicious way to enjoy great fish! Lovely, thick halibut fillets are combined with a creamy lemon and mustard sauce that bakes completely in the oven.
salt and freshly ground pepper, as needed, use less if using salted butter
To serve:
parsley, finely chopped
fresh lemon slices, cut in half-moon
Instructions
Preheat oven to 400F (non-convection/not fan-assisted).
Tip! If using thawed frozen fish, thaw completely, then pat dry really well with a paper towel to remove any excess moisture.
Pat the halibut fillets dry and season with a bit of salt and pepper. Place into a baking dish that is not too large, but allows the fish to have a bit of room between the fillets. Scatter the shallots over the fish and into the baking dish. Set aside.
Add the sauce ingredients to a microwaveable bowl or a small saucepan on the stovetop. Microwave the sauce for 30 seconds, stir, then microwave about 15 seconds more or until the butter is melted and the sauce is smooth. (For the stovetop, heat over medium heat, stirring, until the butter is melted and the sauce is smooth.)
Pour the sauce over the top of the fish, allowing it to spill over into the baking dish. (The sauce will be thin at this point, but it will thicken a bit as it cooks with the fish.) Place into the preheated oven and cook until cooked through, 10-20 minutes, depending on the thickness of the fish (count on about 10 minutes for every inch of thickness). The fish should register 145F internal temperature when tested with an instant-read thermometer, or look for the fish to be opaque, and it should flake easily with a fork. The finished sauce should have thickened, but it won't ever be super thick or gravy-like. It is a perfect consistency for spooning over the fish. See the Recipe Tips if you'd like a bit thicker sauce.
To serve, sprinkle with parsley and place a half-moon lemon slice on top of the fish, if you like. Finish with a bit more salt and pepper, to taste.
Notes
Nutritional information based on two 6oz halibut fillets.Note 1: Heavy whipping cream is recommended as the higher fat content prevents the sauce from splitting when combined with acidic lemon juice. While you can use a lighter cream, the sauce may split. It will still taste fine, but will be less smooth. Canned full-fat evaporated milk is a decent lower-fat alternative.Tips!The finished sauce should be a perfect consistency if using halibut, as it is a firm fish and doesn't release a lot of liquid as it cooks. If you are using another type of fish that releases more liquid, your sauce may be thinner. If you'd like to thicken the sauce slightly, remove the fish from the baking dish and return the baking dish to the oven for a couple of minutes (watch closely!).This recipe is adaptable to other fish options, but avoid thin and tender fish fillets such as sole. Salmon and trout won't fare well as they are too fatty and will make a poor sauce. Thick fillets of cod, tilapia or snapper are good options for this cooking method.Be sure to read the notes above this Recipe Card for more tips, substitution suggestions and step-by-step photos that you might find helpful.