There’s something special about the aroma of onions cooking on the stove top. It often gets me curious about what Mom is cooking! What I really love about this sweet-and-sour red onion relish is that the onions are soft and slightly caramelized, with a hint of vinegar. I love anything with vinegar, especially pickles! 🥒🥒🥒
Not only is this relish super easy to make, it smells delicious and tastes great even by itself. Trust me, you might be tempted to eat several bites while you’re making it, like I was. 😊 It’s fantastic on toasted pumpernickel bread and would make a wonderful addition to a cheese board. For an extra-special garnish, serve it on top of our toast stars with our potato leek soup. Feel free to make up a large batch of it to keep in the fridge for a few days, but it probably won’t last that long!
Sweet-and-sour red onion relish is a delicious condiment on toasted pumpernickel bread or a wonderful addition to a cheese board.
- 1 large red onion
- 2 tablespoons salted butter
- 4 1/2 teaspoons lightly packed brown sugar
- 4 1/2 teaspoons balsamic vinegar
- 1 1/2 teaspoons sherry vinegar
- 1 teaspoon white balsamic vinegar
- 1/2 teaspoon mustard seeds
- 1/8 teaspoon kosher salt
- Chop off the top and bottom of the onion and peel it. Cut it in half from top to bottom, then slice each half into thin strips.
- Over medium heat, melt the butter in a medium frying pan until sizzling. Dump in the onions and stir to coat with the butter. Cook the onions over medium heat for about 3 minutes until they have started to become soft.
- Stir in the brown sugar, balsamic vinegar, sherry vinegar, white balsamic vinegar, mustard seeds, and kosher salt and cook on low heat for 20 minutes, stirring frequently. The liquid should have reduced, and the onions should be soft.
- Serve warm with toasted pumpernickel bread or on a cheese board.
- If you don’t have any white balsamic vinegar, just use regular balsamic. The onions will be darker, but the flavor will be very similar.
- You can also serve this on top of mashed potatoes instead of sour cream or gravy.