Ingredients
Equipment
Method
Make the Sauce
- Combine the red chilies, garlic, and water in a small blender or food processor. Blend until completely smooth. The mixture should look like a thin bright red liquid with no visible chunks. If chunks remain, blend for another 30 seconds.
- Pour the blended mixture into a small saucepan over medium heat. Add the sugar, rice vinegar, tomato paste, and salt. Stir to combine. Bring to a gentle simmer and cook for 5 minutes, stirring occasionally. The sauce will thicken slightly and darken in color as it cooks. Do not boil hard. A gentle simmer extracts the flavor from the chilies without making the sauce bitter.
- Remove from heat and let cool completely before using. The sauce thickens further as it cools. Transfer to a clean sealed jar and refrigerate. The flavor develops and improves over the first 24 hours.
Notes
On chili choice: Bird's eye chilies produce serious heat. Fresno chilies produce a milder, fruitier result closer to the Cholimex standard. A mix of two-thirds Fresno and one-third bird's eye produces the correct balance of heat and flavor. Taste the chilies before blending to calibrate the final heat level.
On the tomato paste: Cholimex, the most widely consumed Vietnamese chili sauce brand, uses real tomatoes in their formula. Tomato paste is the correct home cooking substitute. It adds body, a slight fruitiness, and rounds the sharp edge of the vinegar without making the sauce taste like tomato. One tablespoon is correct.
On sweetness: Vietnamese chili sauce is noticeably sweeter than Sriracha. The sugar is not there to make it a sweet sauce. It is there to balance the heat and acidity. The correct finished sauce should taste spicy first, then sweet, with a clean vinegar note underneath.
On storage: Keeps for 3 weeks refrigerated in a sealed jar. The color will deepen slightly over time but the flavor remains correct.
On store-bought: Cholimex tương ớt and Chin-Su chili sauce are the correct store-bought versions. Both are available at Vietnamese grocery stores. Do not use Sriracha as a substitute. The heat level, sweetness, and flavor profile are different enough to change the finished sandwich.