Mam Tom Dipping Sauce (Fermented Shrimp Paste Sauce)

May 21, 2020

Mam Tom Dipping Sauce © kvalifood.com

Mam tom is Vietnamese fermented shrimp paste - a purple-brown, thick mass that smells intense and tastes far milder than the smell suggests. The dipping sauce is mixed fresh by thinning the paste with lime juice, sugar, garlic and chilli, then whisking it vigorously until it foams and turns lighter in colour. The foam is a sign of quality. The sauce belongs to northern Vietnamese cooking, particularly with bun dau mam tom (rice noodles with fried tofu and boiled pork) and cha ca La Vong (Hanoi’s turmeric fish with dill).

Ingredients

Yields ca. 4 servings as dipping sauce

2 tbsp mam tom (Vietnamese fermented shrimp paste, ~30 g)
1 1/2 tbsp fresh lime juice (~20 ml, ca. 1 lime)
1 tbsp sugar (ca. 12 g)
1-2 tbsp warm water
2 cloves garlic (~10 g), finely chopped
1-2 fresh Thai chillies, finely sliced
1 tsp neutral oil (optional - for the hot oil technique)

Directions

Put the mam tom in a small bowl. Add the warm water and stir until the paste is evenly dissolved.
Add sugar and lime juice. Stir until the sugar is fully dissolved.
Mix in the chopped garlic and chilli.
If using the hot oil technique: heat the oil in a small pan until it just starts to smoke. Pour the hot oil directly into the sauce. This tempers the sharp smell and gives a rounder flavour.
Whisk the sauce vigorously with chopsticks or a spoon for 30-45 seconds, preferably in one direction. The sauce should become lighter in colour and slightly foamy on the surface.
Taste and adjust. More lime if too salty, more sugar if too sharp, a little water if too concentrated.

Notes

Shrimp paste brand: Viet Huong (Flying Lion) is a respected Vietnamese brand. Use Vietnamese mam tom - Thai shrimp paste (kapi) is a completely different thing and will not work here.
Calamansi/kumquat: If you can get calamansi (quat) or kumquats, use them instead of lime. They give a more traditional, rounded acidity.
The foam: The sauce should foam when whisked. If it does not, the paste may be too old.
Storage: Up to 5 days in the fridge. Best made fresh.
The smell: Yes, it smells intense. That is the point. The flavour is far more nuanced than the smell suggests.