This is a nice change of pace from the usual smoky and/or sweet barbecue sauces. The rhubarb gives it thickness and a fruity flavor. The amounts below are suggestions only. Add more honey if you like it sweet, more apple cider vinegar if you like a vinegary kick. Or leave out the ketchup and double up on the mustard and vinegar for a Carolina-style sauce. The sauce is good with grilled pork chops and chicken thighs, but it’s a particularly good match with duck breasts that have been pan-fried and sliced. From Washington Post “In Season” columnist Stephanie Witt Sedgwick, makes about 1 1/2 cups.
Ingredients
2 to 3 teaspoons mild olive oil or vegetable oil
1/2 cup finely diced onion from 1 small (2-ounce) onion
8 ounces rhubarb, thick stalks cut in half vertically, then cut crosswise into 1/4-inch slices (2 to 2 1/4 cups)
1/3 cup packed light brown sugar
1 tablespoon water, plus more as needed for thinning the sauce
2 teaspoons Dijon-style mustard, or more to taste
1 tablespoon apple cider vinegar
1 tablespoon honey, or more to taste
1/2 cup ketchup
1/2 teaspoon salt, or more to taste
Freshly ground black pepper
Apple juice, for thinning the sauce (optional)
Directions
Add enough of the oil to coat the bottom of a medium (2-quart) saucepan; heat over medium heat.
Add the onion and cook, stirring, for 5-6 minutes, until it is translucent and soft, watching closely to make sure it does not brown.
Add the rhubarb, brown sugar and water; increase the heat to medium-high. Allow the sugar to melt, bringing the mixture to a low boil. Cook for 6-7 minutes, stirring every minute or so, until the rhubarb has softened and can be mashed with a spoon.
Remove from heat and let mixture sit in saucepan for 15 minutes. Then add mustard, vinegar, honey, ketchup, salt and pepper to taste, stirring to combine. Transfer to a blender and puree, or use an immersion blender in the saucepan to puree until smooth.
Taste and adjust the seasonings.
To serve, warm the sauce. For a thinner sauce, add water, apple juice, if desired, or the cooking juices from whatever main ingredient the sauce is being served with.
Sauce may be refrigerated in an airtight container for 2 to 3 days.
