Why It Works
- A galangal-infused stock puts the essential flavor of the soup front and center.
- Adding aromatics in stages creates a broth with layered flavors.
- Making the soup with chicken stock and coconut cream creates a broth that's both light and creamy.
Tom kha gai, a Thai chicken soup with coconut and galangal, has gained a spot on nearly every Thai restaurant menu in the West, and I often ask myself…why? The most obvious answer is simple: People like creaminess, as well as sour and salty flavors. Pair those elements with chicken and the almost medicinal flavor of galangal and you have a perfect example of comfort food, a soup that warms your soul and body. However, in my experience, the soup often fails to fulfill its potential. Many renditions contain too much coconut cream, making it feel like I’m sipping a warm smoothie, and they frequently don't have enough of that essential galangal flavor. The galangal isn't negotiable: after all, the soup is called tom kha, which translates to “boiled galangal.”
As I thought about ways to boost the galangal flavor in the soup, I thought of how ginger is sometimes prepared in many Chinese dishes: It's pounded or blended with water before being strained to make ginger water. (Since I'm referring to ginger, I should say this here: please do not let me catch you making this soup with ginger. It's not a substitute for galangal.) I tested this method with galangal by pounding it in a mortar and pestle and then pouring warm chicken stock over the paste to let it infuse. After about 20 minutes, I was left with a concentrated galangal stock that tasted peppery and medicinal; exactly what I want in a tom kha.
Having answered the question of boosting the galangal flavor, I next had to prevent the soup from becoming a coconut smoothie. The solution is simple, cutting the coconut cream with something else to lighten the broth. While some will reach for water here, I choose to build a more deeply chicken-y soup by using a rich chicken stock that's seasoned with fish sauce and packed with aromatics like lemongrass and shallots. The addition of shallots provides undertones of sweetness that echo the later addition of coconut milk without adding extra sugar.
Once the chicken is cooked through, I add the coconut cream, fresh chiles, and makrut lime leaves to the pot. By adding these ingredients at the very end, the delicate flavor of the coconut cream is preserved and the bright and fresh flavors of those finishing aromatics are left intact.
Finally, I season the soup with equal parts fish sauce for saltiness and umami and lime juice for sourness. To make a full meal out of this, I recommend serving the tom kha gai with jasmine rice, green papaya salad, and makheua yao pad tao jiao (stir-fried eggplant).