Tom saep
Non-vegetarian
ต้มแซ่บ · Tom saep
A fiery, sour Isan soup of tender pork ribs in a lemongrass, galangal and lime-leaf broth, seasoned with fish sauce, lime and toasted chilli and finished with herbs.
Tom saep is a Thai soup from Thailand, ready in about 1 hour 25 minutes and made with pork spare ribs, lemongrass and dried whole chillies. It serves 4 and is rated easy to cook.

- Prep
- 15 min
- Cook
- 1 h 10 min
- Total
- 1 h 25 min
- Serves
- 4
- Level
- Easy
- Calories
- 344
Method
Step 1
Blanch the ribs in boiling water for 3 minutes, drain and rinse. Return to the cleaned pot with the water, salt, lemongrass (opens in a new tab), galangal (opens in a new tab), half the lime leaves and the shallots (opens in a new tab).
- 8 min
- high heat
- Stockpot / large pot (opens in a new tab)
Food safety: Wash hands and surfaces after handling raw pork.
Step 2
Simmer gently, partly covered, until the ribs are tender, about 1 hour. Skim as needed.
- 60 min
- low heat
Step 3
Meanwhile, dry-toast the chillies (and rice, if using) in a frying pan until fragrant and darkened, then grind each coarsely.
- 6 min
- medium-low heat
- Frying pan / skillet (opens in a new tab)
- Mortar and pestle (opens in a new tab)
Ventilate the kitchen — toasting chillies makes everyone cough.

How it looks · Photo: https://kaboompics.com/ on Pexels Step 4
Once the ribs are tender, take the pot off the heat and season with fish sauce (opens in a new tab), lime juice (opens in a new tab), ground chilli and sugar (opens in a new tab) to a bold sour-salty-hot balance. Stir in the remaining lime leaves, the toasted rice, coriander and mint (opens in a new tab) and serve.
- 3 min
Add lime off the heat; boiling lime juice turns bitter.
About this dish
- Origin
- Isan (Northeast Thailand), Thailand · Well documentedAlso popular in LaosMore food from Thailand
- Dish
- Lunch · Dinner · Soups · Main courses
- Cooking method
- Simmered, Boiled
- Taste
- sour, spicy (chilli heat), aromatic / warmly spiced, herby
- Diet
- No gluten ingredients · Dairy-free · No nut ingredients · Low-carb · High-proteinWithout the optional extras: No added sugarWorked out from the ingredients. How labels work
All labels
Non-vegetarian · No gluten ingredients · Dairy-free · Egg-free · No nut ingredients · Alcohol-free · Beef-free · Low-carb · High-protein · Calorie-conscious - Good for
- One-pot
- Cook more with
- Pork spare ribs · Lemongrass · Dried whole chillies · Lime juice · Galangal · Makrut lime leaves
Allergens
- Contains, can be adapted: Fishfrom fish sauce
- May contain: Crustaceansfrom fish sauce
Based on typical versions of these ingredients and not verified allergen-free. Brands differ and cross-contact happens, so always check labels. For severe allergies, follow your clinician’s advice.
Nutrition
344 kcal per serving
Estimated1 serving ≈ 556 g · recipe makes 4
Where the energy comes from
- Protein 21%
- Carbohydrate 14%
- Fat 65%
| Nutrient | Per serving | Per 100 g* |
|---|---|---|
| Energy | 344 kcal | 62 kcal |
| Protein | 18.3 g | 3.3 g |
| Carbohydrate | 12.1 g | 2.2 g |
| Net carbohydrate | 10.4 g | 1.9 g |
| Sugars | 3 g | 0.5 g |
| Added sugars | 0 g | 0 g |
| Fibre | 1.7 g | 0.3 g |
| Fat | 24.9 g | 4.5 g |
| Saturated fat | 8 g | 1.4 g |
| Trans fat | 0.2 g | 0 g |
| Cholesterol | 84 mg | 15 mg |
| Sodium | 1261 mg | 227 mg |
| Salt equivalent | 3.2 g | 0.6 g |
Vitamins & minerals per serving
- Potassium
- 590 mg
- Calcium
- 84 mg
- Iron
- 3 mg
- Magnesium
- 64 mg
- Vitamin A (RAE)
- 35 µg
- Vitamin C
- 8 mg
- Vitamin D
- 2.4 µg
- Vitamin B12
- 0.5 µg
- Folate (DFE)
- 31 µg
How these numbers were made
- Calculated from USDA FoodData Central (SR Legacy) per-100 g values and the listed quantities.
- *Per 100 g of combined raw ingredients; the cooked dish may weigh more or less.
- Optional ingredients are not included: sugar, glutinous rice, mint.
- Not counted (tiny amounts or “to taste”): makrut lime leaves.
- Galangal: Fresh ginger used as a stand-in: no galangal entry in FDC SR Legacy, and galangal is a closely related rhizome used in similar small amounts.
- “—” means the value isn’t known for enough of the ingredients; it is never zero by default.
- Values are estimates for guidance, not for medical dosing. U.S. Department of Agriculture, Agricultural Research Service. FoodData Central, 2019. fdc.nal.usda.gov.
Good to know
Tips
- Taste and adjust the fish sauce and lime together until the broth is boldly sour and salty — it should almost make you wince.
Common mistakes
- Boiling the soup after the lime juice goes in, which turns it bitter.
Serve with
- Serve with sticky rice and grilled meats or som tam.
Food safety
- Simmer the ribs until tender and cooked through; refrigerate leftovers within 2 hours.
Storage
- Keeps 2 days chilled; add fresh herbs and lime when reheating.
Reheating
- Reheat until piping hot, then refresh with lime juice.
Variations
- Tom saep nuea: Made with beef and beef tripe instead of pork.
Original editorial recipe · FriendsPantry editorial · Not yet independently reviewed · Added · Updated
Recipe DNA
How this dish is built
Grouped by each ingredient’s role in the dish. Each band’s width is its share of the dish by weight. Choose a component to see what it does.
What the dish is built around
Main ingredient
- Pork spare ribs, cut into short pieces700 g
- Lemongrass, cut into lengths and bruised3 stalk · 60 g
- Lime juice4 tbsp · 61 g
- Glutinous rice, dry-toasted golden and ground (khao khua) (optional)1 tbsp · 12 g
Reviews & corrections
Reviews come from signed-in cooks and appear after a moderator checks them. We never show made-up ratings.
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