Caramelized Onion Jam is a rich, savory-sweet spread made from slowly cooked onions enhanced with vinegar and sugar. Its deep, jammy flavor and luscious texture make it a versatile condiment that transforms everything from toast and burgers to charcuterie boards and main dishes.
Why You’ll Love This Recipe
- Deep, caramelized flavor with a touch of sweetness and tang
- A gourmet addition to sandwiches, meats, and cheese platters
- Easy to make with minimal ingredients
- Keeps well and gets better over time
- Can be canned or frozen for long-term storage
Ingredients
(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)
- Yellow or sweet onions
- Olive oil or butter
- Granulated sugar or brown sugar
- Balsamic or red wine vinegar
- Salt and pepper
- Optional: fresh thyme, garlic, or a splash of wine
Directions
- Prepare onions: Thinly slice onions evenly for even cooking.
- Cook slowly: In a large pan, heat oil or butter over medium-low heat. Add onions and a pinch of salt. Cook, stirring occasionally, for 35–50 minutes until deeply golden and caramelized.
- Add sugar and vinegar: Stir in sugar and vinegar. Simmer until the mixture is thick and jam-like, about 10–15 minutes.
- Finish and store: Taste and adjust seasoning. Let cool slightly before transferring to jars or containers.
Servings and timing
- Makes: About 1½ to 2 cups
- Prep time: 10 minutes
- Cook time: 50–75 minutes
- Total time: 1–1½ hours
Variations
- Use maple syrup or honey instead of sugar for a different sweetness
- Add chopped garlic or shallots for extra depth
- Stir in crisped bacon or a splash of bourbon for a smoky twist
- Try apple cider vinegar or white balsamic for a lighter tang
- Mix in figs or dried fruit for a richer, fruitier version
Storage/Reheating
- Refrigerate in a sealed container for up to 2–4 weeks
- Freeze for up to 6 months
- Reheat gently on the stovetop or in the microwave
- For shelf-stable storage, use proper canning techniques and ensure acidity
FAQs
What’s the difference between caramelized onions and onion jam?
Caramelized onions are slow-cooked until soft and brown, while onion jam is further reduced with sugar and vinegar until thick and spreadable.
How long does it last in the fridge?
Up to a month when stored in an airtight container.
Can I freeze onion jam?
Yes—freeze in small portions for up to 6 months.
What kind of onions are best?
Yellow or sweet onions work best for their balance of flavor and natural sugars.
Do I have to use vinegar?
Yes, it adds acidity to balance the sweetness and acts as a preservative.
Can I use red onions?
Yes—they yield a deeper color and slightly different flavor.
Is this recipe gluten-free?
Yes, as long as your vinegar and other ingredients are gluten-free.
Can I make it spicy?
Add a pinch of chili flakes or cayenne for a touch of heat.
What do I serve it with?
Great with grilled cheese, burgers, crostini, roasted meats, and cheese boards.
How do I know when it’s done?
It should be thick, glossy, and spreadable, with a rich brown color.
Conclusion
Caramelized Onion Jam is a simple yet luxurious condiment that adds gourmet flair to everyday meals. With its deep flavor and versatile uses, it’s the perfect make-ahead spread for both special occasions and casual snacking. Try it once, and it will become a staple in your kitchen.
PrintCaramelized Onion Jam
Sweet, savory, and richly flavored caramelized onion jam—ideal for spreading on toast, serving with cheese, or using as a condiment for sandwiches and meats.
- Prep Time: 10 minutes
- Cook Time: 35 minutes
- Total Time: 45 minutes
- Yield: About 2 cups 1x
- Category: Condiment
- Method: Stovetop
- Cuisine: International
- Diet: Vegetarian
Ingredients
- 4 large yellow onions, thinly sliced (about 800 g)
- 2 Tbsp olive oil
- 2 Tbsp unsalted butter
- 2 Tbsp brown sugar
- 3 Tbsp balsamic vinegar
- 1 tsp fresh thyme leaves (or ½ tsp dried thyme)
- ½ tsp kosher salt (adjust to taste)
- ¼ tsp freshly ground black pepper
- Optional: pinch of red pepper flakes or splash of port/wine for depth
Instructions
- In a large skillet over medium heat, heat olive oil and butter until melted.
- Add the sliced onions, stir to coat, and cook for 5 minutes until softened.
- Reduce heat to medium-low and continue cooking, stirring occasionally, for 25–30 minutes until onions are deep golden—adjust heat to prevent burning.
- Stir in brown sugar and thyme; cook 2 minutes to caramelize sugar.
- Add balsamic vinegar (and optional splash of wine/port), then stir and simmer 3–5 minutes until liquid reduces to jammy consistency.
- Season with salt, pepper, and red pepper flakes if using. Taste and adjust seasoning.
- Remove from heat and let cool to room temperature.
- Transfer to a clean jar; store in the refrigerator for up to 2 weeks.
Notes
- For deeper flavor, substitute half of the balsamic vinegar with red wine or port.
- Use yellow onions for balance; sweet onions yield a milder jam, while red onions add color.
- Make extra and freeze in ice cube trays for easy portions.
- Stir into risotto, top burgers or grilled cheese, or serve alongside sharp cheeses.
- Let it cool fully before sealing the jar to preserve freshness.
Nutrition
- Serving Size: 1 Tbsp
- Calories: 35 kcal
- Sugar: 4 g
- Sodium: 80 mg
- Fat: 2 g
- Saturated Fat: 1 g
- Unsaturated Fat: 1 g
- Trans Fat: 0 g
- Carbohydrates: 4 g
- Fiber: 0.2 g
- Protein: 0.2 g
- Cholesterol: 0 mg