Ingredients

1 medium onion, halved crosswise

1 green bell pepper, halved lengthwise

2 yellow bell peppers, halved lengthwise

1 1/2 pounds vine-ripened tomatoes, halved

4 garlic cloves (unpeeled)

1/4 cup olive oil

Coarse salt and freshly ground pepper

1 fresh serrano chile

1 English cucumber, peeled and cut into 1/2-inch cubes

1 pound large shrimp, peeled and deveined

1/3 cup chopped fresh cilantro

3 tablespoons fresh lime juice, plus lime wedges for garnish (3 to 4 limes total)

Preparation

Heat a grill until medium-hot. Brush vegetables (except the cucumber) and garlic with oil; season with salt and pepper. Wrap garlic in foil. Grill onion, peppers, chile, and garlic, turning once, until soft and charred, 12 to 15 minutes; set aside. Grill tomatoes, turning once, until pale and skins peel, about 6 minutes. Transfer to a food processor; set aside. When cool enough to handle, peel garlic; cut peppers and onion into 1/2-inch pieces. Mince garlic and chile. Transfer all but tomatoes to a large bowl; add cucumber.

Thread shrimp onto skewers. Brush with oil; season with salt and pepper. Grill, turning once, until shrimp are pink and cooked through, 6 to 8 minutes.

Pulse tomatoes until slightly chunky; stir into vegetable mixture. Stir in cilantro, lime juice, shrimp, and 3 teaspoons salt; season with pepper. Garnish servings with lime wedges.