Bring pomegranate juice and 1/4 cup of syrup from jar of mangos to a boil in a saucepan. Cook over medium-high heat until reduced by half, about 10-12 minutes. Reserve 1/4 cup reduced juice for vinaigrette. Stir 1/4 cup oil into remaining juice. Cool to room temperature. Can be made a day ahead; store, covered in refrigerator.

Whisk together 1/4 cup oil, reserved 1/4 cup reduced pomegranate juice, Island Breeze and lime juice. Season with salt and pepper to taste. Can be made a day in advance; store, covered in refrigerator.

Preheat oven to 350 F. Bring water and sugar to a boil; cook until sugar dissolves. Stir in chipotle and cayenne pepper. Add pecans and stir to coat. Remove pecans with a slotted spoon to a parchment-lined baking sheet. Sprinkle with salt and bake 5-7 minutes. Cool. Can be made several days ahead; store in covered container.

With poultry shears, cut off and discard necks of quails. Cut out and discard backbones and halve each quail lengthwise through breast. Arrange quail halves in one layer in shallow, flameproof baking pan. Pour glaze over quail, turning to coat and rubbing glaze into both sides. Marinate quail, covered and refrigerated, for 12 hours. Preheat broiler. Season quail on both sides with salt and pepper. Arrange quail, skin-side up, in pan; discard marinade. Broil quail 3-4 inches from heat 4-5 minutes. Turn quail over and broil 2-3 minutes longer or until cooked to barely pink for medium. Transfer quail to plate. Arrange mâche on 4 serving plates; drizzle vinaigrette over each salad. Drain remaining juice from jar of mangos and discard. Cut mango slices into cubes and arrange over mâche. Sprinkle with shallots and place two quail halves on each salad.