Preheat oven to 350 degrees. Break taco shells into large chips. Combine taco chips, chicken, cheese, stock and taco seasoning in large mixing bowl.
Spread mixture in 9-by-13-inch baking dish. Top with 1-1/2 cups sour cream; pour salsa over sour cream. Bake for 25 minutes, or until hot and bubbling.
Meanwhile, stir lime juice into remaining sour cream. Remove casserole from oven, drizzle sour cream and lime mixture over top and serve at once.