For the salsa, peel the mango, cut the flesh off the stone. Wash the tomato, cut into quarters, remove seeds. Clean and wash the spring onion. Dice or chop everything finely. Mix with 2 tbsp. juice and 1 tbsp. oil. Season to taste with salt and cayenne pepper. Divide into four glasses.
For the avocado cream, wash the dill and cut finely. Cut the avocado in half and stone it. Remove the flesh from the skin and crush finely with a fork. Mix with yoghurt, 2 tbsp. juice and dill. Season to taste with salt and pepper. Divide into four glasses.
Wash the seafood, dab dry. Heat 1 tablespoon of oil and butter in a frying pan. Fry the seafood for 1-2 minutes on each side. Season with salt and pepper. Leave to cool slightly. Put 2 prawns on 1 skewer and arrange on the avocado cream. Skewer the mussels one by one and arrange them on the mango salsa.