2)Place shallots, ginger, garlic, soy, lime juice, and sugar in a blender and blend until smooth.
3)Add the spring onion and oil and blend until combined. Season with black pepper, to taste.
4)Place prawns in a large bowl, pour the marinade over, and marinate at room temperature for 20 minutes.
5)Preheat a grill to high. Remove prawns from the marinade and grill for 1 1/2 to 2 minutes each side. Serve on brown paper bags, if desired.