Gyeoja-jang (Korean Mustard Sauce)

Ingredients

Equipment Needed

• •Small heatproof bowl with a plate or lid
• •Measuring spoons
• •Small whisk or chopsticks
• •Instant-read thermometer, optional

Instructions

1. 1

   Warm the bowl

   Set a small bowl in a larger bowl of hot tap water for 1 minute, then dry it well. This small warmth helps the mustard wake evenly. Do not put the mustard powder straight into a cold bowl and then blame it for sleeping.

2. 2

   Bloom the mustard

   Put the mustard powder in the warm bowl and stir in the warm water until you have a thick, smooth paste. Cover the bowl with a small plate and leave it in a warm spot for 10 minutes. The water should feel warm, not hot: 105 to 113 F. Boiling water dulls the bite, and vinegar added now stops the heat before it begins.

   Notebook 42 says the bloom is the sauce. If the powder does not sit with warm water first, no amount of vinegar or sugar will make it sharp later.
3. 3

   Mix the seasoning

   In a second small bowl, stir together the rice vinegar, soy sauce, sugar, and salt until the sugar dissolves. Mix this separately so the salt and acid go in evenly. A mustard sauce should strike cleanly, not give one spoonful sugar and the next spoonful salt.

4. 4

   Whisk it together

   Uncover the bloomed mustard paste and whisk in the vinegar mixture a little at a time. It will loosen into a glossy yellow-brown sauce. Add the sesame oil only if you are serving it with boiled beef, pork, or pyeonyuk (pressed boiled meat); leave it out for seafood or a chilled vegetable platter, where you want the cleanest heat.

5. 5

   Rest and adjust

   Let the finished sauce sit 5 minutes, then taste it with a slice of cucumber or boiled meat, not from the spoon alone. If it is too thick, whisk in cold water 1 teaspoon at a time, up to 2 teaspoons. If it is too harsh, add 1/2 teaspoon sugar. If it is flat, the bloom failed; make a fresh paste with 1 tablespoon mustard powder and 2 teaspoons warm water, rest it 10 minutes, then whisk it into the sauce.

6. 6

   Serve cleanly

   Spoon the sauce into a small dipping bowl and scatter the crushed sesame over it only if it suits the table. Serve beside naengchae (cold platter), pyeonyuk, boiled seafood, or cold noodles. Dip the edge of the food lightly. Gyeoja-jang should wake the dish, not cover it.

Chef Tips

• •Buy Korean mustard powder, gyeoja-garu, if you can. A mild Western yellow mustard powder will make a softer sauce, and a tube of prepared yeon-gyeoja already contains salt and acid, so it cannot bloom the same way.
• •The water temperature matters. Too cool and the paste stays dull; too hot and the sharpness weakens. Measure it once with a thermometer, then your hand will remember the warmth.
• •For a dinner party, make the sauce 20 minutes before serving. It is strongest the day it is made and loses its high nose-clearing heat as it sits.
• •If you use prepared Korean hot mustard paste instead of powder, start with 2 tablespoons paste, skip the bloom, reduce the soy sauce to 2 teaspoons, and taste before adding salt. It is a useful shortcut, but the flavor is flatter.

Advance Preparation

• •For the best flavor, bloom and mix the sauce 15 to 30 minutes before serving. That gives the mustard time to wake and the seasoning time to settle.
• •The sauce can be refrigerated in a covered container for up to 3 days, but the heat softens each day. For a special table, make it fresh.
• •You can measure the dry mustard powder and mix the vinegar, soy, sugar, and salt several hours ahead. Keep them separate, then bloom the powder close to serving.

Frequently Asked Questions

Nutrition Information

1 serving (about 17g)