This savory fish is the perfect simple meal — easy to make, tasty, and not at all fishy. In the words of Ann, our founder, “This recipe is inspired by an old French menagère... style regional fish cookbook, aimed at young wives (which I was at the time) that I bought on the street in Paris. I still have it. It taught me to lose my fear of cooking fish, and I hope this recipe will do the same for you.”
Preheat the oven to 425 degrees and set a metal baking sheet on a high rack. Cut a sheet of parchment paper to fit the sheet and set aside.
With a sharp knife, make 3 diagonal slashes across the skin side of each fish fillet. Take care to just slash the skin and not cut the fish into pieces. Set aside.
On a cutting board, finely chop the rosemary leaves and garlic together. When they are medium-fine, add the salt and start chopping that in. Lastly, chop in the olive oil until you have a rough paste. (See Chef Tips.) Smear the paste over the skin side of the fish, rubbing it deep into the cuts you made in the skin. Smear any leftover paste onto the flesh side.
Take the hot baking sheet from the oven, quickly cover with the reserved parchment paper, and set the fish on top with skin side down for browning. Squeeze lemon juice over the fillets and bake in the oven on a high shelf until the fish is just done, 8-10 minutes depending on the thickness of the fillet. Serve skin side up with a side of roasted potatoes.
Always remember that fish will continue to cook on the hot surface once it’s out of the oven, so if it’s a little underdone, just leave it for a minute before serving. If it’s just right, serve it quickly.
For step 3, you can also use a spice grinder to blend the rosemary and salt together. Once blended, transfer the rosemary salt to a small bowl, then mix with minced garlic and olive oil to finish making the paste.
You can roast a small whole fish this way instead of fillets. Get the fishmonger to scale and clean the fish. Skip preheating the baking sheet. Slash each side as above and rub in the herb paste. Rub any leftovers into the body cavity along with the lemon rind once you’ve spritzed the fish with the juice. Cook for 20 minutes or until the flesh flakes behind the head.