Peel and prepare the shrimps. Stir lime juice and fish sauce, add pepper and marinate the shrimps for 15 minutes.
Heat sesame oil in a pot and roast the mashed garlic slightly. Add galangal and finely cut lemon grass, roast slightly for another minute. Add chopped plantain and leek and fill up with vegetabel stock, carrot juice and tandoory paste. Boil the soup up and let it simmer for 30 minutes.
Heat frying pan and roast shrimps gently for 2 to 3 minutes on each side. Skewer 2 shrimps on 1 lemon grass stalk.
Puree the soup with a blender and fill it into 4 bowls, place lemon grass stalk over bowl as decoration.