Balsamic Onion Marmalade

If I’m looking to take most any sandwich from eh to “I will remember this forever,” I’ll add Balsamic Onion Marmalade. It has just 6 ingredients (most of which you already have in your pantry) and is basically like a savory onion jam. While I love this sweet onion marmalade for sandwiches, it’s also delicious with roast chicken, on a cheeseboard or slathered on a steak.

In La Jolla, California, it was the Cassius Clay at The Sandwich Club. In Evanston, Illinois, it was the Pesto Chicken at Rollin’ to Go. It seems that I’ve come to associate an “it” sandwich with every city I’ve ever lived in. And New York is no different.

There’s pastrami on rye at Katz’s, or Le Croque Monsieur at Bistro Bagatelle. But at the absolute top of my star sandwich list is the roasted turkey sandwich at Tom Colicchio’s ‘wichcraft. Piled atop a toasted ciabatta roll are thick slices of warmed turkey breast, sliced avocado, crispy bacon, aioli and the final touch that makes this sandwich the ultimate New York City ‘wich—balsamic onion marmalade.

What Is Balsamic Onion Marmalade?

Balsamic onion marmalade is a sweet and tangy condiment made by caramelizing onions and cooking them down with balsamic vinegar and sugar until thick and jam-like.

How Do I Use It?

One of my favorite ways to use balsamic onion marmalade is to spread it on a toasted baguette and top it with creamy brie and slices of avocado. It’s such a simple yet sophisticated appetizer that never fails to impress. I also enjoy pairing it with roasted meats or grilled vegetables, as it adds a gourmet touch to any main course. And of course, it’s a fantastic accompaniment to a cheese platter, offering a sweet and tangy contrast to sharp and creamy cheeses. But the possibilities don’t stop there. It’s also amazing on salads and pizzas, like my favorite French onion pizza recipe!

• Vegetable oil: You need to use just a little oil to cook the onions so they don’t burn. Instead of vegetable oil, you could use canola or avocado oil.
• Onions: As far as preserving onions goes, this homemade onion marmalade is one of my favorite methods. You’ll want white onions for this recipe—not red or yellow.
• Salt: This enhances all other flavors, making this caramelized onion marmalade taste even better. I call for a couple of pinches of kosher salt. If using table salt, use just one pinch. 
• Black pepper: The flavor of freshly ground black pepper cannot be beaten. And I love how the hit of pepper works in this sweet and tangy onion marmalade. If you’re a big black pepper fan, you can use up to 15 grinds.
• Sugar: Without this, this onion jam wouldn’t be much of a jam—more like a flavorful balsamic onion condiment. Use granulated (white) sugar here. 
• Balsamic vinegar: This balsamic onion jam is a versatile condiment for many dishes and it wouldn’t be the same without the sweet, syrupy vinegar that is balsamic. Don’t be afraid of the large amount (2/3 cup) this recipe calls for: It’ll reduce down.

See the recipe card for full information on ingredients and quantities.

1. Cook the onions. After heating the vegetable oil in a large skillet, add the onions, salt and pepper. Cook until the onions are softened (about 20 minutes).

2. Add the sugar. Cook the onions, stirring frequently so the sugar doesn’t burn, for about 10 minutes.
3. Add the vinegar. Add the vinegar and reduce the heat to low. For this best balsamic onion marmalade recipe, the onions will need to continue cooking for an hour The onion marmalade for burgers and sandwiches is ready when the onions are very sticky and jam-like in texture.

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• Warm and Cheesy Onion Dip
• French Onion Mac and Cheese
• Homemade Sour Cream and Onion Dip
• Pickled Red Onion and Carrot Relish

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