Vietnamese Lemongrass and Chilli Oil (aka Chilli Crisp)
This Vietnamese Lemongrass and Chilli Oil, Cộng Sả Ớt Sa Tế in Vietnamese, is a hit of citrusy, lemony, garlicky spicy flavours. Delicious with a bowl of noodles.

- Prep time
- 10 min
- Cook time
- 20 min
- Yield
- 16 servings
- Difficulty
- MEDIUM
Ingredients
- 12 stalk lemongrass ((weight after chopping = 120g/4.2 oz))
- 10 long red chillies ((rough weight 200g/7 oz))
- 2 medium bulbs garlic ((peeled weight ))
- 4 medium shallots ((weight: prepeeled 150g/1.8 oz, peeled 120g/4.2 oz))
- 250 ml vegetable or peanut oil
- 15 g red chilli flakes ((this is about 1/4 cup))
- 1 tbsp sugar
- 2 tbsp fish sauce (OR 1-2 tsp salt (start with 1 tsp))
- vegetable or peanut oil to for sealing
Instructions
- 1
We are going to chop everything coarsely in a food processor/chopper. If yours isn't big enough, do it in batches.Top and tail your lemongrass, slice into rings, and drop into the chopper. Read more on how to do that here.Chop your chillies in 2-3 pieces and drop into the chopper.Peel the garlic and add to chopper.Peel the shallots and add to chopper.Chop everything to a coarse grind.
- 2
Heat the oil in a wok or a saucepan on medium heat. When it's hot enough, add the the chopped aromatics. Reduce the heat to medium-low after 1 minute and cook for 10 minutes, stirring once or twice.
- 3
Add the sugar, fish sauce (or salt) and chilli flakes and cook for another 5 minutes.
- 4
Check seasoning and add more salt or sugar if necessary. Take it off the heat and leave to cool to room temperature.
- 5
Transfer to sterilised jars, top with a layer of vegetable oil and store in the fridge for up to 1 month.