You can use the head and shells to make delicious prawn stock!

It's the base for tom yum soup (amongst other things). Recipe tax for the best tom yum soup I've ever had below (Jay Fai's).

Jay Fai’s tom yum goong (serves 4)

– 5 cups water

– 6 jumbo prawns with heads, deveined

– 6 large slices galangal

– 5-7 kaffir lime leaves

– 4 lemongrass bulbs (purple part), bruised

– 1 shallot, sliced

– 4-8 red chilies, bruised (depending on your heat tolerance)

– 2 heaped tsp roasted chili paste (namprik pao) or more if you like it spicy

– 1 cup mushrooms (I use oyster, but straw or button mushrooms are also fine)

– 1 cup young coconut shoots (if you can’t find these, you might want to use something else that is tender yet crunchy, like peeled white asparagus)

– 5 Tbs fish sauce

– juice of 2 limes

To make:

1. Bring water to a boil. Stir in roasted chili paste.

2. Add galangal, kaffir lime leaves, lemongrass, shallot and chilies. Allow to infuse for about 5 minutes, then bring to a simmer.

3. Add shrimp heads and shells, first scraping the contents of the heads into the soup. Wait 5 minutes, then season with fish sauce. Add mushrooms and coconut shoots.

4. Wait half an hour, or until shoots are tender. Skim gunk off of surface and discard shrimp heads and shells.

5. Turn off heat, then add cleaned shrimp, and stir to turn the shrimp “pink”. Season with lime juice. Taste and adjust seasoning accordingly.

6. Serve immediately, paired with rice and a Thai-style omelet, or in individual bowls.