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.

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.
Caramelized Onion and Tomato Jam

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.
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Use a spice grinder or a mortar and pestle to crush the cumin, coriander, and fennel seeds into a powder.
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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.
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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.
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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.
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Reduce the heat to low and simmer until the mixture is thick and jammy, 40 to 60 minutes.
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Let cool, then refrigerate until ready to use. Serve with crackers or a toasted baguette.
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%)
Recipe Testers’ Reviews
Originally published August 4, 2022
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