Game plan: General canning tips: Before you turn on the heat, be sure to do the following: Read the recipe through, gather all necessary equipment, and check that you have the right amount of each ingredient on hand.
Give all your equipment a once-over: Examine your canning jars for nicks, cracks, uneven rims, or sharp edges that may prevent sealing or cause breakage; check that the lids have no dents and that the sealing compound is even and complete; and check that the bands fit properly.
Finally, have your jars, lids, and bands already sanitized before you start, and prepare only enough for one canner load at a time.
Pearl onion – specific tips: Select pearl onions that are firm, uniform in size, and free of any green sprouts.
1Place salt in a large, nonreactive heat-resistant container and cover with water. Add enough ice to equal 1 gallon total brining liquid. Stir to dissolve salt; add onions. Keep onions submerged by covering with a resealable plastic bag filled with water. Refrigerate and let brine for 12 to 24 hours.
For sanitizing the jars and lids:
1Wash the jars, lids, and bands in hot, soapy water. Rinse well. Dry the lids and bands and set aside.
2Place the jars in a boiling water canner or a 15- to 20-quart pot fitted with a canning rack and a lid. Fill the pot with water and bring to a boil over medium-high heat. Boil for 10 minutes, then turn off heat.
3Keep the jars in the hot water until ready for use, removing one at a time as needed.
For the onions:
1Strain onions and rinse. In a large pot, bring sugar, mustard seed, vinegar, and red pepper flakes to a boil over medium heat and whisk to combine.
2Simmer until sugar has dissolved, about 10 minutes. Keep pickling liquid hot while packing the jars, but do not boil.
3Remove the jars from the hot water with a jar lifter, letting excess water drip off. Bring water in the canner back to a simmer (about 180°F) for processing the packed jars.
4Distribute onions and bay leaves among the sterilized jars, leaving a 1-inch headspace. Cover onions with hot pickling liquid, leaving a 1/2-inch headspace. (If there is leftover pickling liquid, it can be used for a quick pickle. To do so, fill a clean jar with peeled onions, cover with pickling liquid, and refrigerate 12 to 24 hours before eating. Eat within 2 weeks.)
5To remove any air bubbles, slide a clean rubber spatula down the side of each jar and press inward on the onions while rotating the jar; repeat 5 to 6 times for each jar.
For processing the packed jars:
1Wipe the rim and threads of each jar with a clean, damp towel. Place the lids on the jars, checking that the sealing compound is centered. Fit the jars with bands and tighten just until resistance is met.
2Check that the water in the pot or boiling water canner is at a simmer (about 180°F), and set the jars in the canning rack. (The jars must be covered by 1 to 2 inches of water. Add additional boiling water as necessary.)
3Cover the pot with a tightfitting lid and bring to a rolling boil over medium-high heat. Process the jars for 10 minutes at a gentle but steady rolling boil. (Begin calculating the processing time once the water is at a rolling boil. Check occasionally that the water remains at a steady boil.)
4Once processed, remove the jars with the jar lifter and set upright, 1 to 2 inches apart, on a dry towel. Do not retighten the bands; let cool at least 12 hours.
5After the jars have cooled, check for a seal by pressing the center of each lid. If the center is concave and does not flex, remove the band and try to lift off the lid with your fingertips (don’t pull too hard). If you cannot lift the lid, there is a good vacuum seal. If the lid pops off, your jar did not properly seal; eat the onions within two months.
6To store properly processed jars, wipe each lid and jar with a clean, damp cloth (the bands don’t need to stay on for storage), label the jars, and store them in a cool, dry, dark place. Unopened jars can be kept up to a year when stored properly. Once opened, keep in the refrigerator and use within two months.