Slice the cucumbers to ¼”. Thinly slice the onions. Layer with the cucumbers and onions with salt in a deep pan. Let sit for 1 ½ hours.

Wash jars, lids, and rings with warm, soapy water. Fill a water bath canner with water and bring to a simmer. Place the jars inside and keep at a simmer until you are ready to use them. Place the lids in a small saucepot filled with simmering water.

Rinse and drain the cucumber mixture several times to remove any excess salt.

Mix the remaining ingredients in a large saucepan. Bring to a boil. Stir in cucumber mixture and return to a boil. Remove from heat and quickly pack into hot jars. Wipe the rims with a clean, damp cloth, and affix lids and rings.

Gently lower the filled jars into the canner and bring to a boil. Process 10 minutes.