Step 1

Arrange a rack in the middle of the oven and heat the oven to 425ºF.

Step 2

Prepare the following, adding each to a 9x13-inch baking dish as you complete it: Trim, peel, and quarter 2 large shallots lengthwise. Peel and thinly slice 4 garlic cloves. Add 2 pints grape tomatoes, 2 tablespoons to 1/4 cup drained capers (rinse if salt packed), 3 tablespoons of the olive oil, 2 tablespoons red wine or sherry vinegar, and 1/4 teaspoon of the kosher salt. Stir to combine.

Step 3

Roast until the tomatoes soften and split, about 20 minutes. Meanwhile, brush 4 cod fillets all over with the remaining 1 tablespoon olive oil and season all over with the remaining 1/2 teaspoon kosher salt and 1/4 teaspoon black pepper.

Step 4

Stir the vegetables and gently separate the shallot layers with a wooden spoon. Push the tomatoes and capers to the sides of the baking dish and nestle the cod fillets in the center. Return to the oven and roast until the cod is cooked through and flakes easily with a fork, 10 to 12 minutes. Garnish with 2 tablespoons chopped fresh herbs.