Rinse the cucumbers thoroughly with fresh water. Roughly chop the cucumbers, onions, and red bell pepper. Working in batches if needed, transfer the vegetables to a food processor and process until they are diced to your preferred consistency.

Transfer the diced cucumbers, onions, and red bell pepper from Step 1 to a large bowl. Sprinkle with kosher or pickling salt and cover the mixture with water. Let this soak at room temperature for 2-3 hours to help draw out excess moisture.

After soaking, thoroughly drain and rinse the cucumber-onion-bell pepper mixture to remove excess salt. Set aside while you prepare the pickling brine.

In a large pot, combine the vinegar, measured water, raw sugar or maple syrup, minced garlic, dill seed or dill weed, celery seed, and mustard seed. Bring this mixture to a boil to infuse all the flavors.

Stir the drained cucumber-onion-bell pepper mixture from Step 3 into the boiling pickling brine from Step 4. Reduce the heat to low and let everything simmer gently for 10-12 minutes.

Mix the cornstarch and turmeric (if using) with a few tablespoons of water to make a slurry. Add this to the simmering relish, stirring until it begins to thicken. Remove the pot from heat. I find the turmeric adds a beautiful color and mild earthy undertone, but you can leave it out if you prefer.

Ladle the hot relish into sterilized pint-size jars, leaving about ½ inch of space from the rim. Cover each jar with a sealing lid and secure with a canning ring. For refrigerator storage, turn the jars upside down for 15 minutes, then right-side up to cool completely. If the seals are good, label and refrigerate for up to 3 months. If not, refrigerate for up to 4 weeks or process jars in a boiling water bath for pantry storage. For flavor development, I like to let the sealed jars rest for at least 1 week before digging in—the flavors get so much better!