1.Rinse rice under cold running water until water runs clear, drain. Combine rice and the water in a small saucepan, season with salt. Bring to the boil, stirring occasionally. Cover with a tight-fitting lid, reduce heat to low; cook 12 minutes or until water is absorbed. Remove from heat, stand, covered, 10 minutes.
2.Place stock, lemon grass, shallots, bruised garlic, sugar and torn lime leaves in a medium saucepan, bring to the boil. Reduce heat to low, simmer 2 minutes. Add chicken, cook 15 minutes or until cooked through. Remove chicken. Strain broth through a muslin-lined sieve into a large bowl, reserve cooking liquid, discard solids. When cool enough to handle, finely shred chicken.
3.Meanwhile, cook oil and extra garlic in a small frying pan over medium heat, swirling the pan occasionally, for 2 minutes or until light golden. Strain garlic oil through a fine sieve over a small bowl, reserve oil. Drain garlic on paper towel.
4.Return reserved cooking liquid to same medium saucepan with sauce and juice, season to taste. Bring to the boil over medium heat. Stir in shredded chicken, rice, snow peas, buk choy, chilli and extra lime leaves.
5.Ladle soup into bowls, top with coriander, fried garlic and drizzled with a little reserved garlic oil.
Save any leftover garlic oil to drizzle over scrambled eggs or to use in a salad dressing. Any remaining kaffir lime leaves can be frozen for another use. The soup will thicken on standing because of the rice. To prepare this soup ahead, follow the recipe up to the end of step 3, continue with the recipe just before you’re ready to serve.