Stir the olive oil, onion, fennel, garlic, bay leaf, and tomatoes until the ingredients are fully combined. Arrange the sardines in a single layer in a non-reactive dish and pour the prepared tomato-fennel marinade over the fish. Cover the dish and chill it in the refrigerator for 45 minutes to 1 hour.
Heat the grill to high. Remove the sardines from the marinade, pat them dry, and season both sides with the salt and pepper. Remove the bay leaf from the marinade and discard it. Pour the marinade into a skillet set over medium-high heat, and sauté the ingredients until the onions and fennel are tender, about 5 minutes. Set the tomato-fennel garnish aside to cool.
Grill the sardines for 4 to 6 minutes on each side, until the skin is crispy and slightly charred, and the flesh is tender and flakey. Brush both sides of each sardine with the balsamic vinegar before removing them from the grill.
Serve the grilled sardines warm or at room temperature with the tomato-fennel garnish.
Calories from fat
Calories from saturated fat
This easy, protein-rich grilled sardines recipe is a great main course or appetizer. Serve with a simple salad for a light, nutritious meal.