Why This Recipe Works

Homemade mustard is easy to prepare and packs a lot more punch than the store-bought stuff. For our recipe, we start with a 1:1 ratio of milder yellow mustard seeds to more pungent, spicier brown seeds. A little brown sugar tempers the mustard seeds’ bite while cider vinegar (rather than straightforward white vinegar) adds complexity. We soak the seeds before processing them in a food processor with the other ingredients. This step not only softens the seeds but also ensures that they break down evenly when processed. Reserving ½ cup of the soaked seeds and stirring them back into the pureed mustard gives it an appealingly grainy consistency. If sampled right after mixing, the mustard might taste a little bitter. We found it best to let the mustard “ripen” on the counter for a few days to allow bitter compounds to dissipate and spicy ones to develop. Refrigeration will halt these enzymatic reactions, so chill it once it reaches your desired heat level.

Before You Begin

Don’t be tempted to hurry the soaking time by using hot water, as heat activates an enzyme that will kill the mustard’s flavor.

Instructions

Combine vinegar, water, yellow mustard seeds, and brown mustard seeds in medium bowl. Cover with plastic wrap and let stand at room temperature for at least 8 hours or up to 24 hours.

Measure out ½ cup vinegar–mustard seed mixture and set aside. Combine remaining vinegar–mustard seed mixture, sugar, and salt in food processor and process until coarsely ground and thickened, 1 to 2 minutes, scraping down bowl as needed; return to medium bowl. Stir in reserved vinegar– mustard seed mixture.

Using funnel and spoon, portion mustard into two 1-cup jars. Cover and let mustard stand at room temperature until it has reached desired spiciness, 1 to 2 days. (Mustard will become spicier as it rests at room temperature, so refrigerate it once it has reached desired spice level. Once refrigerated, its flavor will continue to mature, but it will not become more spicy. Mustard can be refrigerated for up to 6 months.)