Kaffir lime leaves and fresh lemongrass may be difficult to fine outside of an Asian market. You can substitute with lime peel. In the recipe, you'll be using the juice of a fresh lime. Before cutting the lime, take a vegetable peeler and peel long strips of the lime skin. Use your fingers and squeeze/wring the peel a bit to release its flavors and fragrant oil. Adapted from Everyday Thai Cooking by Katie Chin. The more chile slices you use - and the longer you let it steep in the broth, the spicier it will be.'
Other ingredients you can add: spinach leaves, tofu, shrimp, zucchini slices, bean thread noodles or rice noodles, snow peas, bamboo shoots, etc.
Ingredients:3 cups chicken stock
4 slices fresh ginger
4 kaffir lime leaves, torn (substitute with lime peel)
2 stalks lemongrass, cut into 2" lengths and bruised (substitute with lime peel)
1 fresh hot chile pepper, sliced (I used 2 large slices)
1/2 pound skinless, boneless chicken, cut into bite-sized pieces
1 cup cherry tomato (or 1 whole tomato, cut into wedges)
One 15-oz can straw mushrooms (or handful fresh sliced mushrooms)
3 tablespoons fish sauce
1 lime, squeezed (about 2 tablespoons lime juice)
fresh cilantro leaves
In a pot, add the chicken stock, ginger, kaffir lime, lemongrass and chile slices. Bring to a simmer, cover, and then turn the heat to low. Let simmer for 10 minutes. Strain out and discard the spent herbs. (You can taste the soup at this point, if you would like it more spicy, keep the chile pepper slices in the stock and discard just before serving.)
Add in the chicken pieces, cherry tomato and mushrooms. Bring back to a simmer on medium heat and then cook for an additional 5 minutes.
Stir in the fish sauce, lime juice and cilantro leaves.