Rosemary Marsala Onion Jam

We received a large quantity of organic Walla Walla Sweet onions and needed to find creative ways to put them up, as they have a very short shelf life.  We’ve been drying a ton of them, and pickled some, but I wanted to try an onion jam.  I came up with this and really love it.

I was inspired by a friend’s family recipe for marsala chicken, and based the proportions of ingredients loosely on a recipe for onion thyme jam.


  • 8 medium to large Walla Walla Sweet (or other sweet) onions, diced (about 5 1/2 cups)
  • 1 tsp kosher salt ( 3/4 tsp if using regular salt)
  • 1/2 cup granulated sugar
  • 1/2 cup brown sugar
  • 1 cup Marsala cooking wine (usually found near the vinegar in supermarkets)
  • several twists fresh ground black pepper (probably between 1/8 and 1/4 tsp to taste)
  • 1/2 tsp crushed rosemary

Start the onions cooking in a pot over medium heat.  Add the salt to help draw moisture out of the onions.  The moisture from the onions will keep it moist enough that you shouldn’t need any oil so long as you stir it pretty frequently (especially at first).  As it cooks, you’ll need to tend to it less and less often.  Cook for a good while until the onions are fairly soft and somewhat translucent.  Remove from heat, strain to remove excess liquid, and return to the pot.

Add the remaining ingredients and bring to a boil.  Reduce to low heat and simmer until reduced to a consistency that resembles jam.  There should be just a little bit of viscous liquid on the bottom when you stir it around, but on the whole it should be pretty thick.

Spoon into hot jars leaving 1/2 inch headroom, adjust lids, and process 20 minutes.

Your yield will vary a lot on the size of your onions and how far you reduce it.  My first batch was cut too fine and took more reducing to get the right consistency and only yielded just over two half-pints.  I used a larger dice (hand crank chopper, as opposed to the food processor) on my next batch and got three half-pints.

This stuff is really rich because of how reduced the onions and wine are.  It should be good on herb and other savory breads and baked goods, and is great on crackers.  I imagine it would also make an excellent glaze for meats.

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