Different Types of Thai Soup, Plus a Tom Kha Recipe

Thai soups range from bright, spicy tom yum to mellow coconut-based tom kha, and often balance salty, sour, sweet, and aromatic flavors in one bowl. This recipe makes tom kha gai, a creamy chicken soup with coconut milk, galangal, lemongrass, and lime; cooks adjust its heat and sourness to taste, so it is a useful starting point for exploring the wider family of Thai soups.

Knowing a few soup names makes Thai menus easier to navigate. Tom yum is a hot-and-sour soup, commonly flavored with lemongrass, galangal, and makrut lime leaves; it may be made with shrimp, chicken, or other ingredients, and versions can be clear or creamy. Tom kha gets its name from kha, or galangal, and is known for its fragrant, coconut-rich broth. Tom kha gai is the chicken version, while other versions use seafood or mushrooms.

There are plenty of soups beyond those two. Gaeng jued is a mild, clear soup that may contain tofu, vegetables, glass noodles, or meatballs. Thai noodle soups, often ordered with a chosen noodle and toppings, are another broad category, with broths and seasonings that vary by shop and region. In northern Thailand, khao soi is a curry-noodle soup, commonly served with soft egg noodles, a crunchy noodle topping, and condiments such as lime and pickled mustard greens. Yen ta fo is a distinctive noodle soup with a pink broth associated with fermented tofu sauce. These names describe different styles, not a single fixed recipe for each one.

The recipe below focuses on tom kha gai. Its broth should be aromatic and balanced, not aggressively sweet or so rich that the herbs disappear. Galangal, lemongrass, and makrut lime leaves are traditionally used to perfume the soup; they are usually left in large pieces so they can be set aside while eating. If you cannot find them, the substitutions in the tips section help make a pleasant soup, though the flavor will not be exactly the same.

Ingredients

12 oz (340 g) boneless, skinless chicken thighs, thinly sliced
3 cups (720 ml) unsweetened coconut milk
2 cups (480 ml) low-sodium chicken broth
2 oz (56 g) fresh galangal, sliced into thin rounds
2 stalks (about 30 g) lemongrass, trimmed, bruised, and cut into 3-inch (7.5 cm) pieces
6 makrut lime leaves (about 3 g), torn once to release their aroma
8 oz (225 g) straw mushrooms or cremini mushrooms, halved or sliced
2 medium shallots (about 60 g), thinly sliced
2 Thai bird’s-eye chiles (about 5 g), lightly bruised; use 1 for less heat
2 tbsp (30 ml) fish sauce
3 tbsp (45 ml) fresh lime juice, plus more to taste
1 tsp (4 g) granulated sugar
⅓ cup (10 g) loosely packed cilantro leaves, roughly chopped
2 green onions (about 30 g), thinly sliced
4 cups (about 600 g) cooked jasmine rice, for serving if desired

Instructions

Prepare the aromatics and chicken, keeping the chicken separate from the vegetables and herbs. Trim and bruise the lemongrass with the back of a knife so it releases its scent, then cut it into pieces large enough to spot and remove. Slice the galangal, tear the lime leaves, and cut the mushrooms and shallots. The herb pieces are for flavoring the broth rather than eating, so avoid mincing them.
Pour the chicken broth into a medium pot and add the galangal, lemongrass, and makrut lime leaves. Bring it just to a gentle simmer over medium heat, then lower the heat and simmer for 10 minutes. Keep the liquid below a rolling boil: a quiet simmer extracts the aromatics without reducing the broth too quickly.
Add the coconut milk, mushrooms, shallots, chiles, and sugar. Stir gently and simmer for 6 minutes, until the mushrooms are tender but still hold their shape. Do not let the coconut milk boil hard, which can make the soup look separated and can dull its fresh, fragrant character. Taste a spoonful of broth; it should already taste aromatic, though it will need the chicken and final seasoning.
Add the sliced chicken and simmer gently for 8 to 10 minutes, stirring once or twice so the pieces cook evenly. Check the thickest chicken pieces with a food thermometer; the USDA FSIS safe minimum internal temperature for poultry is 165°F (74°C). If a piece has not reached that temperature, continue simmering and check again rather than relying on color alone.
Turn off the heat. Stir in the fish sauce and 3 tablespoons (45 ml) lime juice. Taste, then adjust with a little more lime juice for a sharper soup, fish sauce for more salt, or a pinch of sugar if the lime tastes especially sharp. Remove the lemongrass, galangal, and lime leaves if you prefer not to leave them in the serving pot. Scatter cilantro and green onions over the top and serve hot.

Tips

Look for the traditional aromatics first. Fresh or frozen galangal, lemongrass, and makrut lime leaves are sold at many Southeast Asian groceries. Frozen aromatics work well straight from the freezer. If galangal is unavailable, use fresh ginger as a practical substitute, but expect a warmer, less citrusy flavor rather than the peppery, pine-like note of galangal.
Use lime leaves thoughtfully. Makrut lime leaves have a fragrant citrus aroma that ordinary lime zest does not quite reproduce. If you cannot find them, add a thin strip of lime zest while simmering, then remove it before serving. Avoid adding a lot of zest, which can make the broth bitter.
Season after the lime and fish sauce go in. Fish sauce brands differ in saltiness, and limes vary in acidity. Add the listed amounts, taste, and adjust in small increments. A well-balanced bowl should taste savory and tangy, with coconut richness and a gentle sweetness in the background.
Keep the coconut broth at a gentle simmer. A hard boil is unnecessary and may cause the coconut milk to separate. If the surface looks slightly uneven, stir gently; it is a texture issue, not a reason to discard the soup.

Serving Suggestions

Serve tom kha gai in warm bowls, with the chicken, mushrooms, and broth divided evenly. Steamed jasmine rice is a simple accompaniment: serve it in a bowl on the side so diners can alternate spoonfuls of rice and soup, or add a small scoop to each serving. Rice helps make the soup a more substantial meal without changing its seasoning.

Put extra lime wedges, sliced chiles, cilantro, and green onions on the table so each person can finish a bowl to taste. If you are serving other Thai dishes, pair this creamy soup with a crisp vegetable salad or a stir-fried vegetable dish rather than another rich coconut preparation. The soup is fragrant and filling, so small portions can also work as a starter before a larger meal.

Explain that the pieces of galangal, lemongrass, and lime leaf are aromatic, not intended as bites. They can be removed from the pot before serving, or left in for a traditional-looking presentation with a reminder to move them aside. If serving children or anyone who prefers mild food, remove the chiles before ladling and offer chili separately.

Variations

Make a seafood tom kha. Replace the chicken with 12 oz (340 g) peeled shrimp or firm white fish cut into chunks. Add shrimp near the end and cook until opaque and safely done; check fish with a food thermometer for 145°F (63°C), the USDA FSIS safe minimum for fish. Shrimp cook quickly, so avoid simmering them for the full chicken cooking time. Seafood has a more delicate flavor, so taste the broth before adding extra fish sauce.

Make it vegetarian. Use vegetable broth, replace the chicken with 12 oz (340 g) firm tofu and extra mushrooms, and swap fish sauce for 1½ tablespoons (22 ml) light soy sauce to start. The result is savory but will not taste exactly like a fish-sauce-seasoned soup. Add soy sauce gradually because it can be saltier than expected, and finish with lime juice as directed.

Turn the flavor toward tom yum. For a hot-and-sour soup, use chicken broth as the main liquid and reduce the coconut milk to ½ cup (120 ml), or leave it out for a clearer broth. Keep the lemongrass, galangal, lime leaves, and lime juice, then build the heat with sliced chiles. Tom yum recipes vary: some include a small amount of evaporated milk or chili paste, while others stay clear, so adjust the style to your preference.

Make a milder bowl. Leave out the bird’s-eye chiles and serve sliced chile or chili paste at the table. For a more filling soup, add cooked rice noodles to each bowl just before serving; keeping them separate until serving helps prevent them from soaking up too much broth. You can also add more mushrooms, but do not crowd the pot so much that the broth stops simmering.

Storage and Reheating

Refrigerate leftover soup within 2 hours of cooking in a covered, shallow container. It keeps for 3 to 4 days in the refrigerator. If possible, store cooked rice separately, since rice left in the soup continues to absorb broth and becomes soft. The coconut broth may separate a little as it cools; that is normal.

Reheat only the portion you plan to eat in a saucepan over medium-low heat, stirring gently until it is steaming throughout and reaches 165°F (74°C), the USDA FSIS temperature for reheated leftovers. Avoid a vigorous boil, which can make the coconut broth look less smooth. Add a squeeze of lime after reheating if the flavor has mellowed. You can freeze the soup for up to 2 months for best quality, though the coconut milk may change texture when thawed; thaw it overnight in the refrigerator and stir gently while reheating.

Frequently Asked Questions

What is the difference between tom kha and tom yum? Tom kha is characterized by galangal and usually has a coconut-rich broth, as in this chicken version. Tom yum is known for a sharper hot-and-sour profile and can be clear or creamy. Both often use lemongrass and makrut lime leaves, but their proportions and other seasonings vary between cooks and recipes.

Can I eat the galangal and lemongrass in the soup? They are added to flavor the broth and are usually left in large pieces because they can be fibrous or tough to chew. Set them aside as you eat, or remove them before serving. Thin slices of galangal may be easier to chew, but the larger aromatic pieces are simpler to identify and remove.

Can I use ginger instead of galangal? Yes. Use the same amount by weight of thinly sliced fresh ginger if galangal is unavailable. Ginger gives the soup a warmer, more familiar spicy note, while galangal has a sharper, more citrusy, pine-like aroma. The soup will still be enjoyable, but its flavor will differ from the traditional version.

Why did my coconut milk separate? Coconut milk can look grainy or split if it is boiled vigorously, especially after it has been simmering for a while. Keep the heat low, stir gently, and avoid prolonged boiling. Slight separation is harmless; stirring the soup while reheating often brings the broth back together enough for serving.

Can I make tom kha gai ahead? You can make it a day ahead and refrigerate it, but the lime and herbs smell freshest when added close to serving. For the best texture, cook the soup through, cool and refrigerate it promptly, then reheat gently to 165°F (74°C). Taste after reheating and add a little fresh lime juice or cilantro if needed.

Is tom kha always made with chicken? No. Gai means chicken, but tom kha can be made with seafood, mushrooms, tofu, or other ingredients. The coconut broth and galangal are central cues, while protein, spice level, and the balance of lime, fish sauce, and sweetness can vary. Choose the version that suits the meal and the ingredients available.

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Safety notes: safe minimum internal temperatures from USDA FSIS; raw and undercooked fish guidance from the U.S. FDA. Food safety notes

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