Recipes › Bulb Onion › Onion Jam
Onion Jam
Sweet, sticky, deeply savory onion jam — the kind of condiment that makes a cheese board transcendent and a burger unforgettable. The onions are cooked down with brown sugar, balsamic vinegar, and thyme until they become a thick, glossy, complex spread. Make a big batch in summer when onions are at peak sweetness and keep it on hand all season.
Bulb Onion is usually ready June to August. More bulb onion recipes, or see what to sow this month where you are.
Ingredients
- 3 lbs yellow or sweet onions, thinly slicedRed onions give a beautiful color
- 3 tbsp olive oil
- 3 tbsp brown sugar
- 3 tbsp balsamic vinegar
- 3 sprigs fresh thyme
- 1 tsp salt
Contains: sulphites.
Method
- Heat olive oil in a large, heavy skillet over medium heat. Add onions and salt. Cook for 25-30 minutes, stirring occasionally, until deeply softened and golden.About 30 min
- Add brown sugar, balsamic vinegar, and thyme sprigs. Stir well and cook over medium-low heat for another 15-20 minutes, stirring frequently, until the mixture is thick, jammy, and glossy.About 20 min
- Remove thyme sprigs. Taste and adjust seasoning. Transfer to a clean jar and let cool before refrigerating.About 5 min
Tips
- Start with a bigger volume than you think — onions reduce dramatically.
- A splash of red wine in place of some of the balsamic adds complexity.
- Use this on burgers, grilled cheese, cheese boards, and toasted baguette.
Ring the changes
- Add a pinch of red pepper flakes for a spicy-sweet jam.
- Stir in a tablespoon of whole-grain mustard at the end for a more savory, tangy version.
Keeping it
Refrigerate in a sealed jar for up to 3 weeks. Can be frozen for up to 3 months.
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