30-Minute Vegan Thai Tom Yum Soup
A light yet comforting vegan Thai Tom Yum soup made with lemongrass, kaffir lime leaves, chili, and fresh vegetables simmered in a fragrant broth. Balanced with sour lime, a hint of sweetness, and optional creamy coconut milk, this plant-based version captures authentic flavors in a wholesome way. Perfect as a starter, main dish, or noodle soup variation.
Equipment
- 1 large pot or Dutch oven
- 1 cutting board
- 1 chef’s knife
- 1 wooden spoon
- 1 Measuring cup set
- 1 Measuring Spoons Set
Ingredients
Aromatics:
- 2 stalks lemongrass tender lower stalks
- 6 cloves garlic crushed
- 10 kaffir lime leaves fresh, frozen, or dried
- 4 Thai chilies or bird’s eye chilies
- 2 –3 slices galangal or ginger with a pinch of black pepper
Soup Base:
- 1 tbsp neutral oil
- 1 small onion cut into wedges
- 3 small tomatoes sliced into wedges
- 6 cups vegetable broth
- 7 oz straw mushrooms or oyster, trumpet, or button mushrooms
- 7 oz baby corn sliced
- 1 tbsp coconut sugar or palm sugar adjust to taste
- ⅓ cup vegan fish sauce plus 1–2 tbsp more to taste
- Salt to taste
- ½ cup fresh lime juice from 2–3 limes, plus more to taste
- 12.2 fl. oz vegan evaporated coconut milk 1 can or 1 cup coconut milk (optional, for creamy version)
- 1 tbsp red chili sauce or chili paste adjust to spice preference
For Serving:
- Fresh cilantro for garnish
- Extra lime wedges optional
Optional Noodle Soup Add-On:
- Thin rice noodles soaked and cooked
- Vegan fish balls or shrimp balls optional toppings
Instructions
- Prepare and Crush the Aromatics: Start by working with the lemongrass, one of the key flavors in this soup. Trim off the tough, woody ends and keep the tender lower stalks near the base. Use the flat side of a knife, a pestle, or the dull end of a cleaver to lightly pound the stalks—this helps release the natural oils and fragrance. Cut each stalk into 3–4 inch pieces. Next, lightly crush the garlic cloves and peel them. Tear the kaffir lime leaves slightly with your hands to help release their citrus aroma. Slice the chilies diagonally (you can keep the seeds for extra heat or remove them for a milder soup). If you have galangal, slice it into thin rounds; if not, use fresh ginger paired with a small pinch of black pepper as a substitute.
- Prepare the Vegetables: Rinse the straw mushrooms thoroughly, then cut them in half. If using oyster mushrooms, simply tear them into bite-sized pieces for a rustic look.Slice the baby corn into thin rounds or small batons so they cook evenly. Cut the onion into wedges and the tomatoes into quarters or small wedges, making sure they’re large enough to hold their shape in the soup. Set all the prepared vegetables aside on a tray for easy access while cooking.
- Sauté the Aromatics and Base Vegetables: Heat a large pot or Dutch oven over medium-high heat and add the neutral oil. Once the oil shimmers, add the onion and tomato wedges. Sauté for 2–3 minutes until the onion begins to soften and the tomatoes release some juices. Now add the garlic, lemongrass, kaffir lime leaves, sliced chilies, and galangal or ginger. Stir-fry for another 2–3 minutes until the mixture becomes fragrant. This step is crucial—it wakes up the aromatics and builds the foundation of flavor for the broth.
- Add Broth and Build Flavor: Pour in the vegetable broth and stir to incorporate all the aromatics. Cover the pot and bring the mixture to a gentle boil over high heat. Once boiling, reduce the heat slightly and let the broth simmer for 8–10 minutes. This allows the lemongrass, kaffir lime leaves, chilies, and galangal to infuse their natural oils and flavors into the liquid, creating the distinctive hot-and-sour base of Tom Yum soup.
- Add Vegetables and Seasonings: When the broth is fragrant, add the mushrooms and baby corn. Stir gently, then season with coconut sugar, vegan fish sauce, and a pinch of salt. Allow the soup to simmer for about 5 minutes on medium heat, or until the mushrooms and corn are tender but not mushy. The sugar balances the sour and spicy elements, while the vegan fish sauce contributes depth and umami. Taste the broth at this stage and adjust the seasoning gradually.
- Stir in Lime Juice, Coconut Milk, and Chili Sauce: Lower the heat slightly and add fresh lime juice, stirring well. This introduces the signature tangy flavor of Tom Yum. For the creamy version, pour in vegan evaporated coconut milk (or regular coconut milk if you prefer a richer, slightly sweeter taste). Finally, stir in your choice of chili sauce or chili paste. Adjust the amount based on your preferred spice level—more for extra heat, less for a gentler flavor. Stir everything thoroughly so the broth becomes well balanced with sour, spicy, salty, and slightly sweet notes.
- Simmer and Adjust to Taste: Allow the soup to simmer uncovered for another 7–8 minutes on medium heat. During this time, the tomatoes will break down further, enriching the broth, and the spices will deepen in flavor. Taste once more and make any final adjustments add extra lime juice for more sourness, more chili sauce for spiciness, a pinch of sugar for balance, or an extra splash of vegan fish sauce for saltiness and umami. This step ensures your soup is perfectly tailored to your taste.
- Remove Tough Aromatics: Before serving, keep in mind that lemongrass stalks, kaffir lime leaves, and galangal slices are not meant to be eaten as they remain fibrous and tough. You can use tongs to remove them from the soup pot, or simply leave them in and remind guests to set them aside in their bowls. Their job is to flavor the broth, not to be consumed directly.
- Serve the Soup Hot: Ladle the soup into bowls while still steaming hot. Garnish with fresh cilantro leaves and provide lime wedges on the side for those who want an extra burst of freshness. This soup is delicious on its own as a light meal or starter, but it can also be made heartier.
- Optional Noodle Soup Variation: For a filling main dish, soak thin rice noodles in boiling water for 7–8 minutes until they turn opaque white and have a chewy bite. Drain well and divide them among serving bowls. Pour hot Tom Yum soup over the noodles and top with your favorite vegan add-ins such as vegan fish balls, shrimp balls, or fried tofu. Finish with a sprinkle of cilantro and a squeeze of lime before serving.
Notes
- Kaffir lime leaves are key to achieving authentic flavor—fresh or frozen is best, but dried can be used if that’s what you have. Always crush the leaves to release their aroma.
- Galangal vs. ginger: Galangal gives a peppery, citrusy note that ginger alone can’t fully replicate. If you can’t find galangal, ginger with a touch of black pepper is a great substitute.
- Creamy version: Traditionally made with evaporated milk, but coconut milk is an excellent vegan alternative. Start with 1 cup and adjust to your preference.
- Chili paste or sauce: Be sure to choose a vegan-friendly option. Sambal oelek or doubanjiang works beautifully if Thai chili paste isn’t available.
- Not all aromatics are edible: Lemongrass, galangal, and lime leaves add flavor but should be removed before eating or set aside in the bowl.
