Preheat the oven to 400°F. Season each of the fillets with salt and pepper. Dredge in spice rub and shake off the excess.
Heat 2 teaspoons of the olive oil in a large skillet over medium heat. Place the fillets in the skillet, skin side down, and pan roast for 1 minute. Turn the fillets and cook for 1 minute longer.
Transfer the fillets to the baking sheet, skin side down, and roast in the oven until the fish is opaque at the center, about 6 minutes (rare) to 8 minutes (medium).
Meanwhile, wipe out the skillet with paper towels. Add the remaining 2 teaspoons olive oil and the garlic to the pan. Place over medium heat. Sauté until the garlic is fragrant and soft, add the spinach, season with salt and pepper, and sauté until the spinach wilts.
To plate, spoon about 2 tablespoons chipotle sauce onto each dinner plate. Arrange the spinach over. Add the tomatoes to the skillet and immediately remove from the heat just to warm them. Arrange the fillets over the spinach, then divide the tomatoes among each plate.
NOTE: I serve this family-style on a larger platter placed in the middle of our table. This is the way we eat at home—simple, not fussy, and good.
Reprinted with permission from Live to Eat: Cooking the Mediterranean Way. 2017 by Michael Psilakis, Little, Brown and Company.