Make Ahead

Balsamic Rhubarb and Onion Ketchup

April 27, 2010
3 Ratings
  • Makes 1 1/2 to 2 cups
Author Notes

This sweet and tart condiment is great on sandwiches made with leftover roast chicken, turkey or pork, and on garlicky grilled brats. Or, thin it down with a bit of apple cider and braise red cabbage in it, to serve with pork chops or herb and garlic sausages. Please note that, like most condiments, this is better after a few days, and is at its best after about a week. Enjoy!!


What You'll Need
  • 2 cups coarsely chopped yellow onions
  • 2 tablespoons olive oil
  • 2 cups of rhubarb, cut into ½” pieces (5 or 6 slender stalks)
  • ½ cup red wine (I use a Côtes du Ventoux)
  • 3/4 cup brown sugar
  • 1 teaspoon kosher salt
  • 1 tablespoon Worcestershire sauce
  • ½ cup red wine vinegar
  • ¼ teaspoon mace
  • ¼ teaspoon allspice
  • 1 tablespoon of brown mustard (I use one with horseradish in it.)
  • 1 tablespoon lightly chopped (or bruised) fresh thyme leaves
  • 3 tablespoons strawberry balsamic vinegar (See note, below.)
  • Raw honey to taste, if necessary
  • Pinch of kosher salt
  • Freshly ground black pepper
  1. In a heavy pot with a lid, cook the onions in the oil with a pinch of salt over medium heat until just translucent, stirring frequently. Then turn the heat down and cook for another thirty minutes, stirring every four or five minutes, taking care not to let them get brown. They should be the slightest golden brown, very soft and sweetly fragrant.
  2. Add the wine, brown sugar, 1 teaspoon of salt, the Worcestershire sauce, wine vinegar, mace and allspice. Cook over medium heat, stirring frequently, for about twenty minutes, until very thick and gooey.
  3. Add the rhubarb and cook for three or four minutes, until just tender. Turn the heat off and cover; let it sit for about ten minutes. Remove the lid, stir well and cook for another minute, stirring constantly.
  4. Add the mustard and thyme leaves; let cool in the pan for about 15 minutes.
  5. Puree in the blender until smooth. Add the strawberry balsamic vinegar and blend for just a few seconds to combine. If it tastes too sharp (vinegary), add a tablespoon or two -- one at a time, tasting after the first -- of raw honey.
  6. Add the ground pepper and blend to combine.
  7. If you plan to vacuum seal for longer term storage, you should put the ketchup back into the pot and heat it to boiling before pouring into sterilized jars and sealing according to the manufacturer's instructions. Or skip the re-heating step and pour into any jar with a vinegar-proof lid and refrigerate for up to four weeks.
  8. Enjoy!
  9. I posted here on food52 a recipe for strawberry balsamic vinegar. If you don’t have any strawberry balsamic vinegar, or don't have time to make it (as it really needs at least three or four days before it's worth using), use regular balsamic vinegar, and drop into the pot, with the mustard, a handful of strawberries that you’ve coarsely chopped.

See what other Food52ers are saying.

  • Lizthechef
  • Sunchowder
  • thirschfeld
  • AntoniaJames

Recipe by: AntoniaJames

See problem, solve problem. Ask questions; question answers. Disrupt, with kindness, courtesy and respect. ;o)

8 Reviews

Lizthechef March 29, 2011
Wondering how this would work if I cut back on the salt and salty ingredients - have you ever experimented with low-sodium condiments? We are on a regime in our household these these days. Thanks!
AntoniaJames March 30, 2011
I think you should try it. It will probably be just fine. Can you put in a good organic tamari instead, or a low sodium soy sauce, right at the end? I'd probably use horseradish (if its sodium content is okay) and mustard seeds, if prepared mustard's sodium level is a problem, and I'd increase the thyme. If you try it, please let us know how it turns out! ;o)
Sunchowder August 22, 2010
I adore rhubarb and really want to try this!
AntoniaJames August 24, 2010
Oh, I hope you do! I make a similar pluot or plum version, also nice and tart-- spare me, please, from sweet ketchups -- which I posted the other day. ;o)
thirschfeld May 16, 2010
Just wanted to let you know I made this and it is amazing. I am always looking for new and good condiments to use up excess garden produce. How many ways have I used this, well let me count the ways, first as bbq sauce on roasted chicken legs, yum. Second I have been brining some home cured hams and, I have to give credit to Amy, my wife, for this idea, I coated one of the smoked hams with it and then rolled it in crushed gingersnaps and then baked it, super delicious Pennsylvania Dutch kinda yum and finally I am going to give it a go round in pork and shrimp egg rolls. So many ways to use this and I am sure I have only hit the tip of the iceberg. Great recipe, thanks so much for posting it AntoniaJames.
AntoniaJames April 29, 2010
Used some of this on a ham sandwich today with a slice of lightly smoked cheese. Am considering using it to glaze a ham . . . . although rhubarb is a vegetable, it says "fruit," but not sweetly, kind of like a pomegranate. ;o)
thirschfeld April 27, 2010
This so makes my day! We are always looking for new ketchups and condiments. I can't wait to give it a go round.
AntoniaJames April 28, 2010
I hope you do! You can substitute a sweet white wine, and white wine or champagne vinegar, if you like, for a lighter version of this with a different character. I usually add a bay leaf to the onion mixture when I do, and throw in a few fresh thyme leaves at the end (leaving out the strawberry balsamic, but using strawberry white wine vinegar, which I also make). Also, feel free to adjust for sweetness. I like a really vinegary ketchup, so be warned . . . ;o)