In a large pot, bring the water or chicken broth to a boil. Add the lemongrass, onion, garlic, and ginger. Let simmer for 5-10 minutes to infuse the broth with flavor.
Add the meat or seafood and cook until just cooked through. Remove from the pot and set aside.
Add the vegetables to the pot and cook until tender.
Add the tamarind paste, fish sauce, sugar, and chilies. Adjust the seasoning to taste.
Return the cooked meat or seafood to the pot and let simmer for 1-2 minutes to heat through.
Remove the lemongrass stalks and discard. Garnish with fresh herbs and serve hot.
Notes
Tips and Tricks
Prepare all your ingredients before you start cooking. This soup comes together quickly, so having everything ready to go will make the process smoother.Use homemade broth if possible. A good broth is the foundation of any soup, and homemade broth will add a lot of flavor to your Cambodian sour soup.Adjust the sourness level to your taste. Some people prefer a more sour soup, while others prefer a milder flavor. Taste the soup as you go and adjust the tamarind pulp or lime juice accordingly.Add the fish sauce at the end. Fish sauce can be quite pungent, so it's best to add it at the end of the cooking process, after you've tasted the soup and determined how much saltiness it needs.Top with fresh herbs and chili flakes. The fresh herbs and chili flakes add a lot of flavor and color to the soup. Be sure to sprinkle them on top just before serving.