Wash the shrimps, dab dry and cut them in half lengthwise. If necessary, remove the dark gut. Peel garlic and chop finely.
Heat 1 tablespoon of oil in a large coated frying pan. Fry the prawns in it over a high heat for approx. 3 minutes, turning them over. Season with salt and pepper. Add garlic at the end and fry briefly. Take everything out and let it cool down a little.
Peel the mango, cut the flesh from the stone and cut into cubes of about 1 cm. Squeeze the lime. Cut avocados in half lengthwise and remove the seeds. Remove the flesh from the peel with a spoon and cut into small pieces.
Sprinkle with half the lime juice. Peel and halve the onion and cut into strips.
Squeeze orange. Mix orange juice, remaining lime juice, salt, pepper and sugar. Fold in 3 tablespoons of oil. Wash coriander, shake dry, pluck off leaves and chop finely. Stir into the dressing.
Mix prawns, mangoes, avocados, onions and dressing. Season again with salt and pepper. Arrange salad in small bowls.