Caramelized Onion and Tomato Jam

This caramelized onion and tomato jam is a tangy, savory spread made with Roma tomatoes, onions, spices, vinegar, and brown sugar. It’s perfect for schmearing on toast rounds or adding to sandwiches.

A wooden cutting board with a bowl of caramelized onion and tomato jam and several toasted baguette slices on it.

Adapted from Joy Howard | Tomato Love | Storey Publishing, 2022

A combination of aromatic cumin, coriander, and fennel seeds along with fresh ginger give this savory-sweet spread its warm, earthy flavor that’s a subtle nod to South Asian cooking. The onions are first caramelized, then cooked low and slow with tomatoes until they break down into a dark, sticky jam. Eat it with crackers or a baguette, or use it to top a burger.–Joy Howard

Onion and Tomato Jam FAQs

How long will tomato jam last in the fridge?

This jam will keep for about two weeks in the fridge. It can also be frozen for 2 to 3 months.

What can I do with tomato jam?

So many things. It can be used as a spread on burgers and sandwiches, served as an appetizer with cheese and crackers, placed in a small dish on a charcuterie board, added to soups and bisques, served on warm toast or biscuits – the possibilities are nearly endless.

How can I tell when a tomato is ripe?

In general, tomatoes should be firm, weighty, and blemish-free. For even more information, read David’s tips here on How to Tell if a Tomato is Perfectly Ripe.

Caramelized Onion and Tomato Jam

A wooden cutting board with a bowl of caramelized onion and tomato jam and several toasted baguette slices on it.
This sweet and sticky no-pectin tomato jam is made with caramelized onions, toasted spices, and slowly simmered Roma tomatoes. You'll be putting it on everything.

Prep 30 mins
Cook 1 hr
Total 1 hr 30 mins
Condiments
American
12 servings | 1 1/2 cups
64 kcal
4.75 / 4 votes
Print RecipeBuy the Tomato Love cookbook

Want it? Click it.

Ingredients 

  • 3/4 teaspoon cumin seeds
  • 1/2 teaspoon coriander seeds
  • 1/2 teaspoon fennel seeds
  • 2 tablespoons canola oil or other mild vegetable oil
  • 2 teaspoons grated fresh ginger
  • 2 medium yellow onions chopped
  • 2 teaspoons kosher salt
  • 1/4 teaspoon red pepper flakes
  • Water
  • 1/4 cup apple cider vinegar
  • 1 1/2 pounds Roma tomatoes seeded, cored, and cut into 1/2-inch (12 mm) dice
  • 1/3 cup firmly packed dark brown sugar
  • Crackers or toasted baguette for serving

Directions
 

  • Use a spice grinder or a mortar and pestle to crush the cumin, coriander, and fennel seeds into a powder.
  • In a large heavy pot over medium heat, warm the oil. Stir in the spices and cook for 1 minute, then add the ginger and cook for 30 seconds more.
  • Toss in the onions, salt, and pepper flakes, and sauté, stirring frequently and scraping the bottom of the pot, until the onions are golden and caramelized, 20 to 25 minutes. If needed, splash in water, 1 tablespoon at a time, and reduce heat to medium-low, if necessary, to prevent burning.
  • Splash in the vinegar and use a wooden spoon to scrape up the browned bits from the bottom of the pan. Stir in the tomatoes and sugar and bring the mixture to a boil.
  • Reduce the heat to low and simmer until the mixture is thick and jammy, 40 to 60 minutes.
  • Let cool, then refrigerate until ready to use. Serve with crackers or a toasted baguette.
Print RecipeBuy the Tomato Love cookbook

Want it? Click it.

Show Nutrition

Serving: 0.25cupCalories: 64kcal (3%)Carbohydrates: 10g (3%)Protein: 1g (2%)Fat: 3g (5%)Saturated Fat: 0.2g (1%)Polyunsaturated Fat: 1gMonounsaturated Fat: 2gTrans Fat: 0.01gSodium: 394mg (17%)Potassium: 180mg (5%)Fiber: 1g (4%)Sugar: 8g (9%)Vitamin A: 487IU (10%)Vitamin C: 9mg (11%)Calcium: 18mg (2%)Iron: 0.4mg (2%)

#leitesculinaria on Instagram If you make this recipe, snap a photo and hashtag it #LeitesCulinaria. We’d love to see your creations on Instagram, Facebook, and Twitter.

Recipe Testers’ Reviews

This caramelized onion and tomato jam didn’t disappoint. I had a good feeling that this easy-to-put-together dish was going to check off all the umami points a good savoury jam needs to have.

A jar of caramelized onion and tomato jam with a spoon resting inside it.

Sweetness from the onions and brown sugar, acidity from the tomatoes and the apple cider vinegar, the warm spices that collect together in a wonderful mouthful to round out this jam. I would most surely add this jam to my burgers, sandwiches, as a pesto to run through a hot bowl of pasta, or even a topping to that breakfast fried egg, or grilled sausage.

This jam is a condiment that will soon be a regular in my fridge this bbq season. I love a great recipe that is adaptable to your spice cupboard, easy to make ahead and gives more back than you give it!

When I saw this caramelized onion and tomato jam recipe I was very excited. I love caramelized onions and the spices, particularly the fennel and cumin were very enticing.

We have been putting this on many things since making it as it adds a touch of rich sweetness. We’ve eaten it with bread, crackers and cheese, rice cakes, deviled eggs, roasted cauliflower, fish, and Brie. I will definitely make this again and a little goes a long way.

All in all, if you’re a fan of sweet relishes, this one is a hit and it has more depth than some of the ones you can buy in the grocery store that are just very sweet and not much else.

I’m a sucker for a savory jam, so when I saw this caramelized onion and tomato jam recipe, I knew I had to try it.

Truthfully, I had already decided what I was making for dinner one night (venison/pork Italian sausage burgers) but I was puzzled about how to take it to the next level. When I saw this recipe, I thought it would be perfect. And, it was. It was so perfect in every way.

I couldn’t find Roma tomatoes, but I wasn’t deterred, and brought home some vine-ripened tomatoes instead. Using the spice grinder was the way to go for me. Do not under any circumstances pull out your pre-ground spices for this. You will miss all the magic!

Watch those onions carefully, and don’t be afraid to use the water as suggested to keep things from burning. Personally, I added a tablespoon of water three different times during the 25 minute cooking time.

The jam mixture is unctuous, thick, sweet, and so complex. The flavor journey of every bite starts with rounded, full, bold flavors from those spices. Then, that’s followed by a punch of sugar and immediate relief from the vinegar. Lastly, there’s a really pleasant amount of heat on the back end.

This tomato jam was really easy to put together and was so delicious. After I made the jam I left it in the fridge for a few days before I tasted it. As soon as I did, I immediately thought of lamb burgers, so on a toasted brioche bun, I put a combo of mayonnaise mixed with sun-dried tomato followed by a juicy lamb patty topped with goat chèvre, crispy lettuce, and this yummy jam…..flavour bomb!

The spices used to make the jam complemented the lamb so well, so much so that I don’t know if I can have my lamb burgers again without this jam. I’ve made tomato jam before but with the use of the spices and the ginger takes this jam to a whole new level.

This savory jam is spectacular; a true flavor sensation for your tastebuds. You have the warm toasted spices in perfect synchronicity with the sweet reduction of tomatoes and caramelized onion, and a nice pop of ginger. I used red onion and it was a lovely component in the jam.

I used the jam on a grilled turkey and cheddar sandwich on sourdough. This is my new favorite sandwich. My barometer is always, “would I order this again from a restaurant?” and the answer is a decisive YES! The caramelized onion and tomato jam is simply the star.

The jam would also be a perfect addition to a cheese board or slathered on a baguette with some goat cheese.

If you’re a condiment lover, give this caramelized onion and tomato jam recipe a try. Even if the combo of fennel, coriander, and cumin sounds a bit ‘unusual’ to you. It really mellows during the cooking.

Don’t skimp on the red pepper flakes, even if you don’t like spicy food. If you try this when it’s hot, the heat is much stronger than after a day-long chill in the fridge. The flakes give a nice burst of flavor and contribute to the ‘tang’.

This does take a while to cook, but you can let it go while you clean the house or read a book or binge-watch your favorite TV show. It will make your kitchen smell a bit vinegar-y, but it dissipates fast.

I would not change a thing about this tomato jam! It is a delicious savory spoonful of bright tomato flavor with warm notes of the onions, spices, ginger, vinegar, and brown sugar. I was tasting spoonful after spoonful from the pot when it was done cooking.

I made a double batch so I could take a jar to my neighbor, where it became part of the Lebanese Easter mezze. Everyone loved it. I loved the jam on burgers, I made them two nights in a row.

I have made several renditions of tomato jam in the past and this one is by far the best. It just blew me away and I want to use it on everything! So far I have used it warm as a spread on toasted baguette, cold on crackers, and as a spread on both burgers and also chicken/mozzarella paninis.

It has just the right zing, tang, sweetness and the texture is both jammy and chunky. It is also simpler than other recipes I’ve tried.

I do recommend adding an additional 5 minutes on medium or medium high heat at the very end to finish off any extra liquid still lurking around, but watch it closely at this point so as not to overdo it.

This recipe was a sleeper hit for me. It fell a little flat and I couldn’t taste the spices right when I was finished. Not bad for sure, but not what I was hoping for. Frustrated, I put it in a container and popped it in the fridge.

Several days later when I came back to it, the spice flavors had bloomed and the jam was very full flavored. It was delicious on its own as well as on crackers with cheese, or in sandwiches. A really good result from just a few basic supermarket staples.

Originally published August 4, 2022

HUNGRY FOR MORE?

Comments

  1. Hello:

    I have lots of leftover pickling spices from putting up cucumbers. Do you think the blend would be a decent sub for the cumin, coriander and fennel?

    1. Tracey, we haven’t tried this, so we can’t say if it would work. My concern would be that the allspice and mustard seeds in pickling spice would overwhelm the flavor of the jam.

  2. 5 stars
    As soon as I saw this recipe posted on Instagram, I knew that I had to make it.
    I’m so glad that I did, it is definitely a keeper!
    I followed the recipe as given, with the exception of the tomatoes. I substituted vine-ripened Campari tomatoes for the Romas.
    The spice blend really makes this savory jam special, so don’t make any changes!
    We enjoyed the jam as an appetizer, on grilled sliced baguette, but I cannot wait to slather it on a burger. Highly recommend!

Have something to say?

Then tell us. Have a picture you'd like to add to your comment? Attach it below. And as always, please take a gander at our comment policy before posting.

Rate this recipe!

Have you tried this recipe? Let us know what you think.

Upload a picture of your dish