Why This Recipe Works

Cooking the fish and vegetables in foil packets keeps the cleanup to a minimum.

Before You Begin

Use extra-small Yukon Gold potatoes measuring 1 inch or less in diameter. If you can find only larger potatoes, cut them in half.

Instructions

Adjust oven rack to lowest position and heat oven to 450 degrees. Line rimmed baking sheet with aluminum foil. Toss potatoes, 1 tablespoon oil, ¼ teaspoon salt, and ¼ teaspoon pepper together on prepared sheet and arrange around perimeter of sheet. Roast until potatoes start to brown, about 10 minutes.

While potatoes roast, cut eight 12-inch squares of foil. Place 4 squares on counter. Divide zucchini, shallot, and peas evenly among centers of squares, leaving 2½-inch border. Sprinkle cod with remaining ½ teaspoon salt and remaining ¼ teaspoon pepper. Place fillets on top of vegetables. Top fillets with tomatoes and drizzle with remaining 2 tablespoons oil.

Place remaining 4 squares of foil on top of each fillet. Pinch and fold top and bottom edges of foil together to create sealed packet. Transfer packets to center of sheet with potatoes. Bake until fish flakes apart when gently prodded with paring knife and registers 140 degrees, about 15 minutes. Sprinkle cod and vegetables with basil and serve with lemon wedges.