Grilled Shrimp and Mango Salad

2 large firm mangoes, peeled & shredded
3 tablespoons thinly sliced green onions
1/3 cup lime juice
2 tablespoons fish sauce (sold in Asian markets)
1 teaspoon sugar
1 small clove garlic, minced
1 small hot chile, such as serrano, seeded, minced
1 pound shrimp, (25 to 30 per pound)
2 cups greens
lime slices, for garnish

Combine green onions, lime juice, fish sauce, sugar, garlic, and chile in a bowl. Mix in shredded mango. Chill while preparing shrimp. Shell and devein shrimp and rinse well; divide into 4 portions. Thread 1 portion onto a slender metal skewer. Run a second skewer through shrimp 1/2 to 1 inch from the first skewer, to keep them flat. Repeat with remaining shrimp. Grill shrimp on a medium hot grill, covered, for about 3 minutes on each side, or until opaque but still a bit moist in the center of thickest parts. Place greens on a platter; mound mango mixture onto the greens using a slotted spoon. Place shrimp over the mango salad and garnish with lime slices, if desired. Serves 4.