Tuna Kabobs with Fresh Lime Sauce

Ingredients

1 pound tuna steaks, cut into 2 x 1 x 1-inch pieces
1/2 pound large shrimp, shelled, deveined, tails left on
1 large green bell pepper (8 ounces), stem, core and seeds removed, cut into 8 wedges
8 to 12 cherry tomatoes, stems removed
3 medium-size white onions (1 pound), peeled and ends removed, quartered
8 to 12 small mushrooms
1/2 fresh pineapple, peeled, cored, cut into 1-1/2 x 1-1/2-inch cubes (about 2 cups). Save rind
1/4 cup freshly-squeezed lime juice
4 tablespoons olive oil, divided
2 tablespoons Worcestershire sauce
1 teaspoon minced garlic (1 medium-size clove)
1 teaspoon ground ginger
1/2 teaspoon coarsely-ground black pepper, or to taste

Place fish, shrimp, bell pepper, tomatoes, onions, mushrooms and pineapple in a shallow dish. Squeeze juice from pineapple rind (about 3 tablespoons) into small bowl. Add lime juice, 2 tablespoons olive oil, Worcestershire sauce, garlic, ginger and black pepper. Mix well; pour over fish, vegetables and pineapple. Cover; marinate at room temperature 30 minutes. Assemble kabobs by alternating fish, shrimp, vegetables and pineapple on metal skewers (or wooden skewers that have been pre-soaked in water). Grill 4 to 5 inches from medium-hot coals or under broiler until desired doneness, about 4 minutes per side, basting frequently with remaining 2 tablespoons olive oil.