1. Prepare the peppers
Wash the peppers thoroughly. Remove the stems and, if you prefer a milder mustard, remove some or all of the seeds. Finely chop the peppers or pulse them in a food processor.
2. Combine the mustard mixture
In a large saucepan, whisk together the yellow mustard, vinegar, sugar, salt, and turmeric.
3. Add the peppers
Stir the chopped peppers into the mustard mixture and place the saucepan over medium heat.
4. Make the thickener
In a small bowl, whisk the flour and cornstarch with the water until completely smooth. There should be no lumps.
5. Thicken the mustard
Slowly pour the flour mixture into the saucepan while whisking constantly. Continue cooking over medium-low heat, stirring frequently, until the mustard becomes thick and glossy, about 8–12 minutes.
6. Simmer gently
Reduce the heat to low and continue stirring for another 3–5 minutes. Do not allow the mixture to scorch on the bottom.
7. Taste and adjust
For more sweetness, add a little sugar. For more tang, add a splash of vinegar. If you want additional heat, finely chop another hot pepper and stir it in.
8. Fill the jars
Ladle the hot mustard into clean jars, leaving appropriate headspace. Wipe the rims clean and secure the lids.
9. Cool and store safely
For a homemade mustard containing flour/cornstarch, do not assume it is safe for shelf-stable water-bath canning. Cool the jars and refrigerate them. Use within a reasonable refrigerated storage period.
Serving Ideas
This mustard is especially delicious served alongside ham, smoked sausage, roast pork, burgers, grilled meats, pretzels, crackers, and sharp cheddar cheese. It also makes an incredible sandwich spread.
For true shelf-stable canning: use a recipe specifically tested for canning safety rather than adapting this formula, because the acidity, ingredients, processing time, and jar size all matter for safe storage.
See more on the next page