To make the shrimp salad: Toss the shrimp with 3 teaspoons (1 tablespoon) of oil in a large bowl to coat. Sprinkle with salt and pepper. Heat a heavy large non-stick skillet over medium-high heat. Saute the shrimp until they are just cooked through or pink, about 1 1/2 minutes per side. Transfer the shrimp to a plate and toss with 1 teaspoon lime juice. Cool completely. Cut the shrimp into small cubes.
To make the parsley sauce: Blend the parsley, sour cream, yogurt, and remaining 2 teaspoons lime juice in a food processor until the parsley is finely chopped. Season the sauce, to taste, with salt and pepper.
Toss the shrimp with the chives, tarragon, capers, and remaining 2 teaspoons of oil in a large bowl to coat. Season the salad, to taste, with salt and pepper.
Separate the endive leaves and arrange on a platter. Spoon about 1 generous tablespoon of the shrimp salad atop each leaf. Drizzle the parsley sauce over the salad and serve immediately.
Recipe courtesy of Giada De Laurentiis