• If you do not plan to can this recipe, skip to MAKE THE JAM.

PREP FOR CANNING

• Fill a canning pot with water, set the lid in place, and heat on high heat until boiling. It can take awhile for the water to come to a boil, so get it started before you begin making the jam.
• Gather the jars you'll use, making sure each is clean and free of nicks in the rim, which could impede sealing.
• Wash the lids and rings in hot soapy water. (If you're using non-Ball brand lids, prepare as suggested by manufacturer.)

MAKE THE JAM

• Put olive oil and onions in a large, heavy bottomed saucepan, Dutch oven, or large skillet over medium heat, stirring only occasionally; cook until golden, about 45 minutes.
  4 pounds sweet yellow onions, 4 tablespoons extra virgin olive oil
• Add sugar and balsamic vinegar and cook for another 45 minutes or more, until thickened and somewhat syrup-y. Add salt, pepper, and herbs.
  1 1/2 cups granulated sugar, 1 1/2 cups balsamic vinegar, 2 tablespoon finely minced summer savory, 2 teaspoon sea salt, 1 teaspoon ground black pepper
• Proceed with canning steps or cool and transfer to an airtight container for refrigerator storage.

CANNING THE JAM

• Ladle hot jam into quarter-pint, half-pint, or pint sized jars, leaving 1/4" head space. A canning funnel makes this easy.
• Wipe jar rims to remove any jam that may have spilled. A clean rim is essential to a good seal.
• Set jar lids in place. Screw bands on finger tight.
• Use a jar lifter to gently submerge jars into hot water in the canning pot. Water should cover the top of the jars by an inch. The water will cool somewhat in reaction to the addition of the jars. Return the water to a simmer and then set the timer.
• Process for 10 minutes 0-1,000 feet altitude; add an additional minute for every additional 1,000 feet in elevation.
• Remove jars from water using the jar lifter and transfer to a solid, towel-covered surface. Allow to cool for 24 hours.
• Check seals. Lids should be solid and pulled down tight. (if they flex and pop, the jar didn’t seal; put unsealed jars in the refrigerator and use those first).
• Remove rings and wash outsides of jars. Store in a cool, dry place.