Start by washing and peeling the onions. If you’re using small onions (about 1-inch in diameter), they’re perfect for this process. Larger onions will need to be cut into halves or quarters to fit in jars more easily.

Place the peeled onions into a pot and cover them with boiling water. Bring the water back to a boil and let the onions boil for about 5 minutes. This helps to preserve the flavor and texture during the canning process.

After boiling, carefully pack the onions into hot, sterilized jars, leaving about 1-inch headspace. Be sure to pack them tightly but not so much that the onions are crushed.

If you’d like to add salt, put 1/2 teaspoon into pint jars or 1 teaspoon into quart jars. This step is optional, but it adds flavor to the onions as they preserve.

After packing the onions and adding the salt, fill each jar with boiling water, leaving that crucial 1-inch headspace.

Use a clean spatula or chopstick to gently stir the contents of the jar to release any trapped air bubbles. Then, wipe the rims of the jars with a clean cloth to ensure there are no residues that could prevent a proper seal.

Place the lids on the jars and tighten the rings just to fingertip-tight.

Now, place the jars into a pressure canner.

Process pints for 40 minutes and quarts for 40 minutes at 11 pounds of pressure (dial gauge canner).

For weighted gauge canners, use 10 pounds of pressure at altitudes from 0-1,000 feet, and 15 pounds of pressure above 1,000 feet.

Make sure to adjust the pressure based on your altitude for best results.

Once the canning time is up, allow the canner to cool and depressurize naturally. Afterward, carefully remove the jars, check the seals, and let the jars cool completely before storing them in a cool, dry place.