Super-moist, delicately cooked fish, this Poached Cod Fillets with Sherry-Tomato Vinaigrette recipe from Cook’s Illustrated (CI) was just the ticket for Meatless Monday. Any meaty white fish such as halibut, sea bass or snapper would also work, but cod tends to be the most economical—at least in our ‘hood.
The restaurant-style dish typically requires a pot of pricey olive oil. And even 3/4 cup may seem like a lot, but CI found that using a smaller skillet, dropping in half an onion, and flipping the fish halfway puts a nice dent in the supply needed. Plus they employed that same oil to crisp flavorful garnishes and finally blend into a creamy vinaigrette.
Speaking of garnishes, only four ounces of artichoke hearts seemed miserly at best, and many reviewers agreed. So I tripled the amount to 12 ounces, and patted myself on the back for doing so because they were the BOMB! That decision of course made it necessary to increase the volume of corn starch.
And we have been trying to locate frozen artichokes for months now, none of our local grocery stores carry them anymore—odd indeed. So if you find you’re in the same pickle, purchase the jarred version, but don’t get the marinated variety. It is essential that you drain them really well and blot them with paper towels before coating them with the corn starch. (Later found out Trader Joe’s carries frozen artichokes.)
A few other alterations included boosting the quantity of cherry tomatoes and an extra garlic clove (pretty much a staple move on our part). In addition, I placed the platter of covered, cooked cod into the turned-off oven along with the dish of artichokes to keep warm while we made the vinaigrette.
My changes are noted in the ingredients list below. And while serving the meal with couscous or steamed white rice is great to sop up all that luscious vinaigrette, we went low-carb and made a side of sautéed baby spinach.

Poached Fillets with Sherry-Tomato Vinaigrette
Ingredients
Fish
- 1 1/2 lbs. skinless white fish fillets, 1 inch thick
- Kosher salt
- 12 oz. frozen artichoke hearts, thawed, patted dry, and sliced in half lengthwise
- 2-3 Tbsp. cornstarch
- ¾ cup olive oil
- 4 garlic cloves, minced
- ½ onion, peeled
Vinaigrette
- 5 ounces cherry tomatoes
- ½ small shallot, peeled
- 4 teaspoons sherry vinegar
- Kosher salt
- ½ teaspoon pepper
- 1 tablespoon chopped fresh parsley
- 4 ounces cherry tomatoes, cut into 1/8-inch-thick rounds
Directions
FOR THE FISH:
- Adjust oven racks to middle and lower-middle positions and heat oven to 250 degrees. Pat fish dry with paper towels and season each fillet with 1/4 teaspoon salt. Let sit at room temperature for 20 minutes.
- Meanwhile, toss artichokes and cornstarch in bowl to coat. Heat 1/2 cup oil in 10-inch nonstick skillet over medium heat until shimmering. Shake excess cornstarch from artichokes (mine didn’t have any excess to shake off) and add to skillet; cook, stirring occasionally, until crisp and golden, 2 to 4 minutes.
- Add garlic and continue to cook until garlic is golden, 30 to 60 seconds. Strain oil through fine-mesh strainer into bowl. Transfer artichokes and garlic to an ovenproof plate lined with a paper towel and season with salt. Do not wash strainer.
- Return strained oil to skillet and add remaining ¼ cup oil. Place onion half in center of pan. Let oil cool until it registers about 180 degrees, 5 to 8 minutes.
- Arrange fish fillets, skinned side up, around onion (oil should come roughly halfway up fillets). Spoon a little oil over each fillet, cover skillet, transfer to middle rack, and cook for 15 minutes.
- Remove skillet from oven. Using 2 spatulas, carefully flip fillets. (Don’t sweat it if the fillets fall apart, it’s almost impossible to flip them completely intact.)
- Cover skillet, return to middle rack, and place plate with artichokes and garlic on lower-middle rack. Continue to cook fish until it registers 130 to 135 degrees, 9 to 14 minutes longer.
- Gently transfer fish to serving platter, reserving 1/2 cup oil, and tent fish loosely with aluminum foil. Turn off oven, place the platter of fish in oven while also leaving plate of artichokes inside.
FOR THE VINAIGRETTE:
- Process whole cherry tomatoes, shallot, vinegar, 3/4 teaspoon salt, and pepper with reserved 1/2 cup fish cooking oil in blender until smooth, 1 to 2 minutes. Add any accumulated fish juice from platter, season with salt to taste, and blend for 10 seconds. Strain sauce through fine-mesh strainer, pressing on solids to extract as much liquid as possible (discard solids).
- To serve, pour vinaigrette around fish. Garnish each fillet with warmed crisped artichokes and garlic, parsley, and tomato rounds. Serve immediately.
Adapted from a recipe by Cook’s Illustrated