• Slice 2 pounds cucumbers into ¼-inch rounds and place in a large bowl.* Sprinkle cucumbers with ¼ cup pickling salt and toss to coat. Cover and refrigerate for 2 hours. Once chilled, transfer the cucumbers to a colander, rinse well under cold water, and let them drain thoroughly.
• Wash the jars, lids, and screw bands in hot, soapy water and rinse well. Place the jars in a canner, cover with water, and bring to a boil. Keep the jars hot until you're ready to fill them. In a small saucepan, bring the lids and screw bands to a gentle boil, then remove from the heat and set aside.
• In a large pot, combine the 2 cup sugar, 1 cup pickling vinegar, 1 cup apple cider vinegar, 2 teaspoons mustard seeds, 1 teaspoon celery seeds, ½ teaspoon red pepper flakes, and 3 cloves. Bring to a gentle simmer over medium heat, stirring until the sugar has completely dissolved.
• Add 2 cups sliced onion and cucumbers to the pickling liquid. Bring everything to a boil, then remove from heat.
• Using a slotted spoon and a wide-mouth funnel, pack the hot cucumbers and onions into the warm jars, leaving about 1 inch of space at the top. Ladle the hot pickling syrup over the vegetables until the jars are filled to within ½ inch of the rim.
• Run your finger around each jar rim to check for chips or cracks, then wipe the rims clean with a paper towel dipped in the sterilized water from the canner. Place a clean lid on each jar and screw on the band until it's finger tight. Repeat with the remaining jars.

Refrigerator Pickles

• For refrigerator pickles, let the jars cool completely, then refrigerate for up to 3 months.

Pantry Pickles

• If you'd like to store the pickles in the pantry, process the jars in a boiling water bath. Return the filled jars to the canner, making sure the water covers them by at least 1 inch. Bring the water to a full boil and process for 15 minutes.
• Carefully remove the jars with jar lifters or tongs and place them on a towel-lined counter to cool completely before storing.
• Listen for the lids to 'pop' which means they have sealed properly. You can also test by pressing down on the lid. If it does not pop back, it has sealed.