Method:
Preheat the Oven: Start by preheating your oven to 375°F (190°C).
Prepare the Fish: If you're using whole mackerel, clean and fillet the fish. Season with salt and pepper on both sides.
Prepare the Sauce: Heat olive oil in a pan over medium heat. Sauté the garlic and onion until softened, about 5 minutes. Add the crushed tomatoes, oregano, and red pepper flakes (if using). Season with salt and pepper and let the sauce simmer for 10-15 minutes, allowing the flavors to meld together.
Bake the Mackerel: In a baking dish, place the mackerel fillets. Pour the tomato sauce over the fish. Cover with aluminum foil and bake for 20 minutes.
Finish and Serve: Remove the foil and bake for another 10 minutes, allowing the sauce to thicken and the fish to fully cook. Garnish with fresh basil leaves before serving.
Variations and Tips:
Substitutions: If you're looking for a lighter version, you can substitute the mackerel with any firm white fish, like cod or haddock. For a richer sauce, you can add a splash of white wine or some black olives.
Make it Spicy: If you enjoy a bit of heat, add red pepper flakes or a fresh chili to the sauce.
Herb Variations: Fresh parsley or thyme can be used instead of basil for a different herbal note.