I turned plain onions into a sticky-sweet, deeply savory jam that makes every simple meal sing.

Jump to Recipe

I am obsessed with caramelized onions. The punch they bring to everything.

I adore the way slow-sweetened yellow onions turn almost savory-sweet, dark and sticky, a flavor that sneaks into sandwiches, pizzas, and bowls and refuses to leave. And I love a splash of balsamic vinegar for that sneaky tang that makes each bite sing.

No fluff, just intense, layered onion flavor that transforms plain food into something worth pausing for. I catch myself spooning them straight from the pan.

I am ruined for raw slices forever. Every meal becomes selfishly better; I hoard them on toast, burgers, and salads.

Ingredients

Print Recipe (No Advertisments)

Onions: deep sweet base, caramelizes into jammy goodness you’ll want on everything.
Butter: adds silky richness and a toasty, rounded mouthfeel.
Basically pure comfort.
Olive oil: keeps things slick without burning, brings subtle fruity notes.
Salt: amps flavor, helps sweetness pop.
Don’t skip it if you want balance.
Basically sugar: optional nudge for quicker browning and a touch of sweetness.
Plus liquid: adds moisture, loosens stuck bits, and adds savory depth if broth.
Vinegar: bright little punch, cuts sweetness and gives real rounded finish.

Ingredient Quantities

2 large yellow onions (about 1 lb / 450 g), thinly sliced

2 tbsp unsalted butter

1 to 2 tbsp olive oil

1/2 tsp fine salt, more to taste

1 tsp granulated sugar (optional, helps with browning)

1 to 4 tbsp water or low sodium vegetable/chicken broth (as needed to deglaze)

1 tbsp balsamic vinegar or red wine vinegar (optional, for depth)

How to Make this

Print Recipe (No Advertisments)

1. Slice 2 large yellow onions thinly, keep pieces fairly even so they cook the same.

2. Heat a wide skillet over medium heat, add 2 tbsp unsalted butter and 1 to 2 tbsp olive oil until butter melts and foams.

3. Add the onions and 1/2 tsp fine salt right away, stir to coat in the fat, spread them into an even layer.

4. Turn the heat to medium low and let them cook, stirring every 4 to 6 minutes so the onions brown slowly without burning. This takes about 30 to 45 minutes total depending on how dark you want them.

5. If onions start sticking or look dry, add 1 to 4 tbsp water or low sodium vegetable/chicken broth to deglaze the pan and scrape up the brown bits. Use small splashes when needed.

6. About 10 minutes before they are done, sprinkle 1 tsp granulated sugar if you want a bit more browning and sweetness, it helps but is optional.

7. When onions are deeply golden and jammy, stir in 1 tbsp balsamic vinegar or red wine vinegar for depth and taste, cook 1 more minute to meld flavors.

8. Taste and add more salt if needed, remove from heat and let cool a little before using. They keep in the fridge for up to 5 days or freeze for longer.

9. Quick tricks: use a heavy wide pan for even browning, be patient, lower heat if you see black bits, and deglaze often enough to avoid burning but not so much you steam them.

10. Serve warm on burgers, pizza, in soups, or just straight from the spoon because honestly they are that good.

Equipment Needed

1. Chef’s knife (sharp)
2. Cutting board
3. Wide heavy skillet (cast iron or heavy-bottomed stainless steel)
4. Wooden spoon or heatproof spatula
5. Heatproof spatula or tongs for stirring and scraping
6. Measuring spoons (for butter, oil, salt, sugar, vinegar)
7. Liquid measuring cup or small ladle for adding water/broth to deglaze
8. Small bowl or plate to hold sliced onions before cooking
9. Airtight container or jar for storing leftovers

FAQ

Q: How long does it take to caramelize onions? A: About 30 to 60 minutes depending on heat, pan size and how deeply caramelized you want them. Plan at least half an hour.

Q: Can I speed it up? A: You can raise the heat but you risk burning and losing sweetness. A faster method is to add a pinch of sugar and a splash of water often, but the flavor won’t be quite the same.

Q: Do I have to add sugar or vinegar? A: No. Sugar just helps browning, vinegar adds depth at the end. Both are optional, the slow cooking alone makes them sweet.

Q: Why are my onions soggy instead of brown? A: Usually the pan is crowded or the heat is too low so they steam. Turn up heat slightly and spread them out, or cook smaller batches.

Q: Can I use other onions? A: Yes. Yellow and sweet onions are best for caramelizing. Red onions work too and give a different flavor and color. White onions are fine but less sweet.

Q: How do I store them? A: Cool completely then refrigerate in an airtight container for up to 1 week. Freeze in small portions for up to 3 months.

Q: What can I use caramelized onions for? A: Everything from burgers, grilled cheese, tarts, pizzas, soups, roasted veggies, to mixing into dips and mashed potatoes. They add a savory sweet boost.

SO MUCH FLAVOR! HOW TO MAKE CARAMELIZED ONIONS Recipe Substitutions and Variations

Onions: try shallots for a milder, sweeter result or red onions for a bit more bite; sweet vidalia or Walla Walla onions work great too if you want extra sweetness.
Unsalted butter / olive oil: use ghee or clarified butter for nuttier flavor, or coconut oil for a slightly sweet twist; for dairy free go with a neutral oil like avocado oil.
Granulated sugar: swap with a teaspoon of honey or maple syrup if you want a more complex sweetness, or skip it entirely and add a splash of balsamic later to boost browning.
Balsamic or red wine vinegar: substitute sherry vinegar or apple cider vinegar for bright acidity, or use a squeeze of lemon juice for fresh tang if that’s what you got.

Pro Tips

1) Use a wide, heavy pan so the onions spread out in a single layer. Crowding traps steam and you’ll get soft limp slices instead of those rich brown bits you want.
2) Be patient and keep the heat low. If you see black specks, you rushed it. Stir every 4 to 6 minutes but let them sit long enough to brown first — little pauses make a big difference.
3) When the pan looks dry, add tiny splashes of water or broth and scrape up the browned bits. Too much liquid and you’ll steam them, too little and they’ll burn, so go slow.
4) Finish with a splash of vinegar and a pinch of salt after theyre jammy, not while theyre raw. The acid brightens the sweetness, and you can always add more salt later if needed.

SO MUCH FLAVOR! HOW TO MAKE CARAMELIZED ONIONS Recipe

Recipe by Ashley Gaintor

0.0 from 0 votes

I turned plain onions into a sticky-sweet, deeply savory jam that makes every simple meal sing.

Servings

servings

Calories

151

kcal

Equipment: 1. Chef’s knife (sharp)
2. Cutting board
3. Wide heavy skillet (cast iron or heavy-bottomed stainless steel)
4. Wooden spoon or heatproof spatula
5. Heatproof spatula or tongs for stirring and scraping
6. Measuring spoons (for butter, oil, salt, sugar, vinegar)
7. Liquid measuring cup or small ladle for adding water/broth to deglaze
8. Small bowl or plate to hold sliced onions before cooking
9. Airtight container or jar for storing leftovers

Ingredients

2 large yellow onions (about 1 lb / 450 g), thinly sliced
2 tbsp unsalted butter
1 to 2 tbsp olive oil
1/2 tsp fine salt, more to taste
1 tsp granulated sugar (optional, helps with browning)
1 to 4 tbsp water or low sodium vegetable/chicken broth (as needed to deglaze)
1 tbsp balsamic vinegar or red wine vinegar (optional, for depth)

Directions

Slice 2 large yellow onions thinly, keep pieces fairly even so they cook the same.
Heat a wide skillet over medium heat, add 2 tbsp unsalted butter and 1 to 2 tbsp olive oil until butter melts and foams.
Add the onions and 1/2 tsp fine salt right away, stir to coat in the fat, spread them into an even layer.
Turn the heat to medium low and let them cook, stirring every 4 to 6 minutes so the onions brown slowly without burning. This takes about 30 to 45 minutes total depending on how dark you want them.
If onions start sticking or look dry, add 1 to 4 tbsp water or low sodium vegetable/chicken broth to deglaze the pan and scrape up the brown bits. Use small splashes when needed.
About 10 minutes before they are done, sprinkle 1 tsp granulated sugar if you want a bit more browning and sweetness, it helps but is optional.
When onions are deeply golden and jammy, stir in 1 tbsp balsamic vinegar or red wine vinegar for depth and taste, cook 1 more minute to meld flavors.
Taste and add more salt if needed, remove from heat and let cool a little before using. They keep in the fridge for up to 5 days or freeze for longer.
Quick tricks: use a heavy wide pan for even browning, be patient, lower heat if you see black bits, and deglaze often enough to avoid burning but not so much you steam them.
Serve warm on burgers, pizza, in soups, or just straight from the spoon because honestly they are that good.

Notes

Below you’ll find my best estimate of this recipe’s nutrition facts. Treat the numbers as a guide rather than a rule—great food should nourish both body and spirit. Figures are approximate, and the website owner assumes no liability for any inaccuracies in this recipe.