This Onion Jam Is The Best Appetizer [Recipe]

If you like onions, then you probably like the sound of a caramelized onion jam. If onions aren’t your thing, though, be prepared to have a tasty new exception to the rule. Plus, what better way to save all your onions from going bad?

Bring on the jam!

To make this jam, I like to use red onions. These onions are firmer and a bit tangier than yellow or Vidalia. However, you may not always be able to find these onions, in which case, I suggest you use yellow, Vidalia, or even shallots.

Text area that says "Onion Jam The Best Appetizer, Vegan and Gluten-free, 5 simple ingredients, makes 3-4 Jars ," followed by red onion jam in a clear glass jar

When it comes to caramelizing, you probably already know that the key ingredient is a sweet and sour agent. In this case, I chose brown sugar and balsamic vinegar because the two mix just right. If you don’t have these ingredients, choose granulated sugar, caster sugar, or even a touch of honey. As for the balsamic, it is a bit pricey, so you can try red wine vinegar or apple cider vinegar instead.

All that is left is the seasoning, which isn’t always necessary for caramelized things, but I think it adds a great final aroma. I use thyme to cook along with the onions, but other herbs that work are rosemary, dill, or basil.

Now all you have left to do is cook everything together until the reduction becomes sweet and thick. Be careful with this step, as these onions can turn from deliciously caramelized to burning very quickly. You should keep a close eye on your stove as you cook and turn the heat down if things seem to be burning.

Once done cooking, make sure your jars are sterilized and hot. Ladle in the onion jam and flip them upside down in boiling water to process for about 10 minutes.

Enjoy this caramelized onion jam on a baguette, toast, as a topping on meat, or salads!

Looking for more jam and jelly recipes? We got more of them HERE.

Onion Jam

Recipe by Gillian Lightman


  • 1.3 lbs (587 g) red onions, sliced thinly

  • 1 tbsp olive oil

  • 1 spring fresh thyme

  • 2 tbsp brown sugar

  • 2 tbsp balsamic vinegar


  • Heat olive oil in a saucepan over medium heat.
  • Add onions and thyme.
  • Cook while stirring occasionally for 15-20 minutes.
  • Add sugar and continue cooking for another 3 minutes.
  • Add vinegar and 1/2 cup (118 ml) cold water.
  • Bring to boil.
  • Once it’s boiling, reduce heat to low and simmer for 5 minutes uncovered until it’s thick.
  • Gently ladle into hot jars.
  • Process for 10 minutes (Adjust for altitude).
  • Turn heat off, let jars sit for 5 minutes to settle.
  • Remove jars and cool for 24 hours. Do not place jars on a cold surface or where there’s cool draft as jars may crack.
  • After 24 hours, check seal on lids by pressing down the center. The lids shouldn’t wiggle and must feel nice and and solid.
  • Any unsealed jars must be refrigerated and consumed first.