Thai Prawn and Mushroom Soup

This Thai prawn and mushroom soup is like a warm embrace from your favorite Thai restaurant—fragrant with lemongrass and galangal, creamy from coconut milk, and loaded with succulent prawns and earthy mushrooms. It sits somewhere between Tom Yum and Tom Kha, taking the best elements of both for a soup that's rich without being heavy.

Best of all, it comes together in just 30 minutes. The aromatics infuse the coconut broth in 10 minutes, the prawns and mushrooms cook in 3. It's the kind of recipe that makes you wonder why you ever ordered takeaway.

Tom Kha vs Tom Yum: Understanding the Difference

Thai cuisine has two famous hot-sour soups: Tom Yum with its clear, spicy broth, and Tom Kha with its rich coconut base. This prawn and mushroom soup follows the Tom Kha tradition, where coconut milk creates a luxuriously creamy backdrop for the bright Thai aromatics.

The coconut milk softens the edges of the lime and chilli, creating a more mellow, rounded flavor profile. It's milder than Tom Yum but equally satisfying—perfect for those who prefer richness over heat.

The Holy Trinity: Galangal, Lemongrass, Lime Leaves

These three aromatics are non-negotiable for authentic Thai soup. They infuse the coconut broth with complex, layered flavors that simply cannot be replicated with substitutes.

Galangal: Often confused with ginger but distinctly different—galangal has a piney, citrusy quality with hints of pepper. It's less fiery than ginger and more aromatic. Slice it thin so it infuses well.

Lemongrass: Use only the white bottom portion. Bruise the stalks with the back of a knife to release the essential oils. The citrusy, grassy aroma is unmistakably Thai.

Kaffir Lime Leaves: These glossy, figure-eight shaped leaves add an intense citrus perfume. Tear them to release their oils. Fresh or frozen work best; dried are a poor substitute.

Protecting the Coconut Milk

The biggest mistake home cooks make with coconut milk soup is boiling it vigorously. High heat causes the fat to separate from the liquid, creating an oily, curdled mess instead of a silky broth.

Keep the heat at a gentle simmer—you should see bubbles lazily breaking the surface, nothing more. This maintains the creamy emulsion and produces that restaurant-quality smoothness.

Perfect Prawns Every Time

Prawns overcook quickly, going from succulent to rubbery in seconds. Add them to the gently simmering broth and watch carefully. They're done when they curl into a loose C-shape and turn pink—about 3 minutes.

Use green (raw) prawns, not pre-cooked. Raw prawns absorb the flavors of the broth as they cook and have a much better texture than reheated pre-cooked ones.

Mushroom Matters

Traditional Thai soups use straw mushrooms, which have a lovely crunchy-slippery texture. Since these are hard to find fresh outside Asia, button mushrooms make an excellent substitute—they're mild enough not to compete with the aromatics.

Slice them fairly thick so they maintain some texture after cooking. They only need a few minutes in the hot broth.

The Final Balance

Thai soups require tasting and adjusting at the end. The fish sauce provides saltiness, the palm sugar sweetness, and the lime juice brightness. Add each off the heat, then taste. Too salty? Add more lime. Too sour? Add more sugar. The goal is harmony.