Open the fridge in any Vietnamese household and you are sure to find a jar of nước mắm. I’m not talking about the pure bottled stuff, but rather the mix that accompanies many dishes on our dining table. It is often served as a dipping sauce for chả giò (eggrolls) or as a sauce drizzled over dishes, such as cơm tấm bì (broken rice with shredded pork) or bánh xèo (savory crêpes). Though the base sauce is only composed of a few simple ingredients (lime juice + sugar + water + nước mắm), achieving a harmonious balance among these contradictory ingredients is not an easy feat for the untrained palate. Getting it just right requires a bit of finesse that comes with practice.
Undeniably, my mom’s nước mắm is second to none. Even my father-in-law declared it the best nước mắm on the planet when he mistakenly thought that my mother-in-law had made it. The only problem is, my mom doesn’t have a written recipe. Like all of the cooking that she does, she makes her nước mắm from instinct and tasting. Measuring cups and the such have never figured in her repertoire of cooking tools. That made it rather difficult for me to learn how to make a proper nước mắm, especially since she is thousands of miles away and her instructions over the phone always go something like, “add a little bit of this and a little bit of that until it tastes good.” With such imprecise instructions, my inconsistent results were often less than satisfactory.
Since I wasn’t able to replicate my mom’s nước mắm based on her vague instructions, I started to tinker with different combinations of the ingredients. After quite some time, I finally came up with something that approaches that of my mom’s! What’s great about the recipe is that it takes the guess work out of balancing the ingredients and it takes no more than 5 minutes to make.
Nước Mắm Sauce
1 part sugar
1 part hot water + 3 parts room temp water
1 part nước mắm
garlic, finely minced
chili peppers, finely chopped
*If using vinegar, reduce to 1/2 part.
Combine the lime juice with the sugar. Then add the hot water and stir. Once all of the sugar has dissolved, add the rest of the water. Stir in the nước mắm. Depending on the saltiness of the nước mắm that you use and what the sauce will be served with, it may be necessary to add a little more nước mắm. If it will be served simply as a dipping sauce, the recipe above should suffice. However, if it will be served over vermicelli noodles with a heaping load of fresh herbs and lettuce, the sauce will need to be a little saltier. If I’m making about 500 ml of nước mắm, I tend to add about another tablespoon or two of nước mắm if it will be drizzled over a noodle dish. Once the sauce is to your tasting, add the minced garlic (about 2-3 cloves per 500 ml) and chili peppers.
I usually store the sauce in a jar, which should keep for about a month or so in the fridge.