8 cups chicken stock or low-sodium chicken broth (64 fl oz)
4 cups water
1 tablespoon Thai green curry paste*
4 garlic cloves, coarsely chopped
1 (2-inch) piece peeled fresh ginger, coarsely chopped
1 teaspoon coriander seeds, crushed
2 cups loosely packed whole fresh cilantro leaves plus 1/2 cup chopped (from 2 large bunches)
1 cup jasmine rice
3/4 lb boneless skinless chicken breast, thinly sliced crosswise, then slices cut lengthwise into thin strips, or 3/4 lb medium shrimp in shell (31 to 35 per lb), peeled and deveined
1 (13- to 14-oz) can unsweetened coconut milk, stirred well
1/4 lb snow peas, trimmed and cut diagonally into 1/4-inch strips
2 tablespoons Asian fish sauce
2 tablespoons fresh lime juice
1 1/2 teaspoons salt, or to taste
Accompaniment: lime wedges
Combine stock, water, curry paste, garlic, ginger, coriander seeds, and whole cilantro leaves in a 3- to 4-quart saucepan, then simmer, uncovered, until ginger is softened, about 15 minutes. Pour through a paper-towel-lined sieve into a 5- to 6-quart heavy pot and discard solids. Stir rice into soup and simmer, uncovered, stirring occasionally, until tender, about 15 minutes.
Add chicken or shrimp and poach at a bare simmer, uncovered, until just cooked through, about 3 minutes. Stir in coconut milk, snow peas, and fish sauce and simmer, uncovered, until peas are crisp-tender, about 2 minutes. Remove from heat and stir in lime juice, salt, and chopped cilantro.
*Available at Asian markets, some specialty foods shops, and some supermarkets.