Peel onion, garlic cloves and 1 piece (approx. 2 cm) of ginger. Clean, wash and seed the Hokkaido pumpkin. Peel and wash the potatoes. Dice everything roughly and fry in hot oil. Season with salt, pepper and cayenne pepper. Unsweetened coconut milk, 1⁄2 l stir in water and vegetable stock. Bring to the boil, cover and cook for about 30 minutes.
Finely puree the soup. Season to taste. Wash prawns, dab dry. Fry in hot oil for about 2 minutes. Season with salt and pepper. Put on wooden skewers. Serve soup with prawns.