Remove the glaze from the shrimp under running water and allow to thaw in a sieve on a plate for about 1 hour.
Now make the marinade: mix lemon juice, vinegar, oil, chilli, parsley and soy sauce, press in the garlic clove and season with salt, pepper and sugar. The marinade should be fresh and spicy so that it can still give the shrimp plenty of flavor.
Mix with the prawns and leave to stand in a not too shallow container in the refrigerator for at least 2 hours, stirring occasionally.