Possibly defrost the prawns. Clean, wash and cut salads into bite-sized pieces. Peel onions
Mix vinegar, mustard, salt and 1 pinch of sugar. Fold in 2 tablespoons of oil. Finely dice 1 onion and stir in. Divide the remaining onion into eight. Wash and halve the tomatoes
Cut the shrimps lengthwise on their backs and remove the black intestine. Wash the prawns. Fry in 1 tablespoon of hot oil on each side for about 2 minutes. Season with salt and pepper. Take out and keep warm
Briefly fry the tomatoes and onion loaf in the cooking fat. Season with salt and pepper and remove. Drizzle salads with marinade. Spread the tomatoes, onions and prawns on top