Jammy Caramelized Onions
Transform humble onions into a rich, sweet, and savory jam-like condiment perfect for elevating burgers, cheese boards, or simple toast with this patient, low-and-slow cooking method.
For 10 servings
Peel and halve the yellow onions. Using a sharp knife or mandoline, slice them thinly and uniformly, about 1/8 inch thick. Uniform slices ensure even cooking.
Heat the olive oil in a large, heavy-bottomed skillet or Dutch oven over medium-low heat. Add the sliced onions and about half of the salt. Stir well to coat the onions with oil.
Cook, stirring occasionally, for 10-15 minutes until the onions soften and become translucent. Do not allow them to brown at this stage.
Reduce the heat to low. Continue to cook, stirring every 5-7 minutes, for another 30-40 minutes. The onions will gradually release their moisture, shrink in volume, and turn a deep golden-brown as their sugars caramelize. If they start to stick to the bottom of the pan, add a tablespoon or two of water or vegetable broth to deglaze, scraping up any browned bits.
Once the onions are deeply caramelized, very soft, and a rich brown color, increase the heat slightly to medium-low. Add the balsamic vinegar, brown sugar (if using), the remaining salt, and black pepper. Stir thoroughly.
Continue to cook, stirring constantly, for another 5-7 minutes, allowing the liquid to evaporate and the mixture to thicken into a glossy, jam-like consistency. The onions should be tender and deeply flavored.
Taste and adjust seasoning as needed. Remove from heat and let the jammy caramelized onions cool completely before transferring them to an airtight container.
Store in the refrigerator for up to 1 week. These onions can also be frozen in small portions for up to 3 months.
What to keep in mind.
4 tips from the recipe — small details that make a real difference to the final dish.
- 1Patience is Key: Caramelizing onions properly takes time. Resist the urge to increase the heat, as this will burn them rather than caramelize them, resulting in a bitter taste.
- 2Uniform Slicing: Ensure all onion slices are roughly the same thickness. This allows them to cook evenly, preventing some pieces from burning while others are still raw.
- 3Heavy-Bottomed Pan: Use a large, heavy-bottomed skillet or Dutch oven. This distributes heat more evenly and prevents hot spots that can cause burning.
- 4Deglaze as Needed: If the onions start to stick or develop dark spots too quickly, add a splash of water or vegetable broth to scrape up the fond (browned bits) from the bottom of the pan. These bits are full of flavor!
Adapt it for your goals.
Herb Infused
Add a sprig of fresh rosemary or thyme during the last 15 minutes of cooking for an aromatic twist. Remove the sprig before serving.
Spicy KickSpicy Kick
Stir in a pinch of red pepper flakes along with the balsamic vinegar for a subtle heat that complements the sweetness.
Wine EnhancedWine Enhanced
Replace 1 tablespoon of balsamic vinegar with 1 tablespoon of dry red wine (like Merlot or Cabernet Sauvignon) for a deeper, more complex flavor profile.
Why this is on our healthy list.
Rich in Antioxidants
Onions are packed with antioxidants, including quercetin, which helps combat free radicals and reduce inflammation in the body.
Digestive Health
They contain prebiotics, which feed beneficial gut bacteria, promoting a healthy digestive system and improved nutrient absorption.
Low in Calories
Despite their rich flavor, caramelized onions are relatively low in calories, making them a delicious and healthy addition to many dishes.
Frequently asked questions
Yellow onions are generally preferred for caramelizing due to their higher sugar content, which results in a deeper, sweeter flavor and better browning. Sweet onions like Vidalia or Walla Walla also work well.


