Tom Yum Soup

Tom yum is a Thai soup with shrimp and a broth that features salty, sour, sweet, and spicy flavors. “Tom” translates to “boiled” and “yum” translates to “medley,” which refers to the soup’s dressing. Yes, this soup has a dressing. Thai salads are called yum, and yum vinaigrette is made up of fish sauce, lime juice, palm sugar, and chilies. Add boiling hot broth to it and you’ve got tom yum, or “salad soup.” 

In addition to the yum, the soup features herbs — lemongrass, cilantro, and makrut lime leaves — that give it a bright aroma. The makrut lime plant is used more for its leaves than its fruit. The leaves offer a strong, earthy-citrus scent and can be found in many Asian grocery stores (either in the produce section or frozen).

The flavor of tom yum should be sour upfront from lime juice, then salty from fish sauce, with a mild sweetness from nam prik pao paste. You might not be able to necessarily taste the lemongrass and makrut lime leaves, but these aromatics should hit your nose while you slurp.

These are the two most popular soups outside of Thailand, and while they both contain similar ingredients (lemongrass, makrut, lime juice, Thai chilies), there are distinctions that set them apart.

• The main difference between the two soups is galangal, a fragrant root, which tom kha is named for. Tom yum sometimes has galangal too, but it’s not the star ingredient.
• Tom yum contains nam prik pao paste (also known as chile jam), which is a roasted chile paste that contains dried shrimp, shallot, garlic, and tamarind. 
• Tom yum is often made with shrimp, while tom kha is commonly made with chicken.
• While tom yum can sometimes have coconut milk, tom kha always has coconut milk.

The beauty of many Thai dishes is that they freeze really well. All of the aromatics (lemongrass, makrut, chiles) freeze beautifully, so you should buy them in bulk and keep them wrapped and frozen. The soup itself is also amenable to being frozen — just keep the shrimp out, which might turn mealy upon reheating.