Instructions: With a paring knife, make an incision through the shell along the back of the prawns. Devein, leaving the shell intact; rinse the prawns and pat dry.

Whisk together the sugar and fish sauce in a bowl until the sugar is completely dissolved. Stir in the oil and lemongrass. Add the prawns, and toss running your fingertips between the flesh and shells. Place the prawns in a plastic bag and seal the bag. Marinate the prawns, refrigerated, 2 to 3 hours, turning the bag over every 30 minutes or so.

Grill over a barbecue (make sure the flames have subsided, and coals are red with white ashes), or in a well-oiled grill pan over medium-high heat, until prawns are cooked through and turn pink, about 3 minutes per side for king prawns, and 2 minutes for medium prawns. Serve with star fruit on the side.

Variation: Muc nuong xa, grilled lemongrass squid, is equally delicious. Substitute 1 pound whole squid, skinned and cleaned, for the prawns. In Step 2, marinate for 1 hour, and in step 3, grill for 1 to 2 minutes, depending on the size of the squid.

This recipe yields 4 to 6 servings.

Comments: The best prawns for this recipe are king prawns, measuring about 8 to 9 inches long. Plump and tender but firm, their heads that are full of sweet tomalley. If these are not available, use medium prawns, usually about 5 to 6 inches long. Marinated in a combination of lemongrass, fish sauce, and sugar, either is excellent grilled over a barbecue or in a grill pan any time of the year.

If you cannot find fresh or frozen lemongrass, substitute garlic or ginger; although much different in flavor, the result will be equally tasty. The optional star fruit slices are used not only as a beautiful garnish but also because the sourness is a perfect compliment to the sweetness and saltiness of the dish.

If you would like to email yourself the recipe for later use, or share the recipe with your friends or family, enter the email addresses below and this recipe will be emailed to you and others as well.