1½pods sour tamarindyou can find this in a Thai or Asian grocery store
350gramspork ribs
2stalks lemongrass
3-4slicesgalangal
6kaffir lime leaveshand torn and bruised
½tablespoonsalt
1teaspoonsugar
5Thai bird's eye chilesroughly pounded
100gramsmushroomany kind you prefer
Instructions
Add 1½ liters of water to a pot and simmer the pork ribs with the lemongrass, galangal, kaffir lime leaves and tamarind pods for about 50 minutes. Remove any fat floating on top of the liquid.
Use a slotted spoon to scoop the tamarind pods from the soup and hold the spoon just right above the surface of the soup. Use another spoon to squash the tamarind pulp through the slotted spoon into the soup and discard the membranes and seeds.
Season the tom yum with salt, sugar and Thai bird's eye chiles.
Add the mushrooms and let cook for about 1-2 minutes before turning off the heat.
Notes
If the tom yum isn't sour enough for you, you can add fresh lime juice to it and keep tasting as you go.