Roasted Rhubarb Barbecue Sauce

Spring brings those first rhubarb stalks that are bright, tart, and just begging to be used beyond dessert. This recipe takes fresh rhubarb, roasts it alongside garlic to enhance the sweetness and soften it up, then purees it for a smooth base. From there, it’s simmered with familiar BBQ ingredients for a tangy, well-rounded sauce that’s as vibrant as it is delicious.

The sauce is a perfect blend of sweet and tangy, naturally thickened by the roasted rhubarb puree. It’s a quick way to enjoy rhubarb in savory dishes—brush it on grilled chicken or pork, slather it on your burgers and ribs, use it as a marinade, or serve it alongside your favorite fries and wings as a dip.

Keep reading for a straightforward ingredient list and step-by-step instructions. Plus, I’m sharing handy tips for roasting and blending, tasty flavor twists, and storage advice. This recipe yields roughly 2 cups and keeps for about a month in your fridge. There are also notes on freezing and canning if you want to stock up!

Fresh rhubarb is roasted, then pureed and cooked with traditional barbecue sauce ingredients in this unique and flavorful condiment.

Why You’ll Love This Sauce

This Roasted Rhubarb Barbecue Sauce stands out with its bright, lively flavor and a hint of sweetness that’s just enough to balance the tartness. Roasting the rhubarb really deepens its natural fruity notes while softening it so it blends perfectly into a creamy base that thickens the sauce naturally. New to working with rhubarb? See our guide on how to prepare, store, freeze, and cook with rhubarb.

It’s wonderfully flexible—you can drizzle it on grilled chicken, pork chops, or burgers, toss it with wings, use it to marinate, or even serve it as a zesty dip. Prefer a chunkier, spoonable condiment? Try our Rhubarb Relish.

Thanks to the rhubarb’s natural pectin and roasting process, there’s no need for cornstarch or thickeners—just pure, concentrated flavor.

What You’ll Need

• 4 cups coarsely chopped rhubarb stalks
• 3 cloves garlic
• 1 cup water, with extra on hand if needed
• 3 tablespoons balsamic vinegar (apple cider vinegar works too)
• 1/2 cup brown sugar (either light or dark)
• 1/4 cup ketchup or substitute with tomato sauce
• 1 tablespoon Worcestershire sauce
• 1 tablespoon chili powder (adds warm depth)
• 1/4 teaspoon ground cinnamon (a subtle twist)
• A dash of cayenne pepper (for a touch of heat)
• Salt and freshly ground black pepper, to taste

Roasting, Blending, and Simmering

1. Preheat oven to 425°F (220°C); line a baking sheet with foil and lightly oil or spray it.
2. Scatter 4 cups coarsely chopped rhubarb and 3 whole garlic cloves evenly on the prepared baking sheet.
3. Roast 15–20 minutes, until the rhubarb is very soft and edges start to caramelize.

4. Transfer the roasted rhubarb and garlic to a blender or food processor.

5. Add 1 cup water and blend until super smooth, adding more water 1 tablespoon at a time if needed to help puree.
6. Pour the rhubarb puree into a medium saucepan.
7. Stir in 3 tablespoons balsamic vinegar, 1/2 cup brown sugar, 1/4 cup ketchup (or tomato sauce), 1 tablespoon Worcestershire sauce, 1 tablespoon chili powder, 1/4 teaspoon ground cinnamon, a dash of cayenne, and salt and pepper to taste; add more water gradually if a thinner consistency is desired.

8. Place the saucepan over medium-low heat and bring the sauce to a gentle simmer.

   

9. Simmer uncovered for 10–15 minutes, stirring occasionally, until the sauce thickens.

10. Remove the pan from heat and let the sauce cool slightly.

    

Pro Tips for Best Results

• Pick firm, crisp rhubarb stalks without any blemishes for the best flavor and color.
• Be sure to roast until the rhubarb is very soft—this makes blending much easier and brings lovely caramelized notes to your sauce.
• If your blender is having trouble pureeing, add water a little at a time instead of all at once to help things along.
• Always taste as you go! You can add a bit more brown sugar if you like it sweeter or some extra vinegar if you want a tangier bite—the same sweet-tart balance you’ll see in rhubarb jam made without pectin.
• Start with a small amount of cayenne pepper. You can always add more after it simmers if you want a little extra heat.
• Use a wide, shallow pan for roasting rhubarb and garlic. This helps them brown evenly without steaming and keeps the flavor bright.

Flavor Twists and Substitutions

• Smoky: Add 1 to 2 teaspoons smoked paprika or swap some ketchup for chipotle in adobo to give your sauce a smoky kick.
• Sweeter: Substitute all or part of the brown sugar with maple syrup or honey to bump up the sweetness naturally.
• More tart: Use apple cider vinegar instead of balsamic and dial back the brown sugar for a brighter, tangier sauce.
• Fruity twist: Toss in a cup of roasted strawberries or peaches when pureeing for a jammy, sweet BBQ sauce variation—think the sweet-tart balance of strawberry rhubarb jam.
• Mustardy tang: Whisk in 1 or 2 teaspoons of Dijon mustard at the end for an extra layer of flavor and zing.

Storing and Preserving

Refrigerate: Once cooled, keep your sauce in an airtight container in the fridge for up to a month. It’s a great make-ahead condiment for busy weeknight dinners.

Freeze: Pour the sauce into freezer-safe containers or ice cube trays for easy portioning. Freeze for up to 3 months. Thaw in the fridge overnight before using.

Canning: If you want to preserve a bigger batch, this sauce works well for water bath canning. Just make sure your jars are fully covered by at least 2 inches of water and boil for 15 minutes. (Don’t forget to follow a reliable canning guide for your altitude—this step-by-step water bath canning process for strawberry rhubarb jam walks through jar prep, headspace, and timing.)

Reheating: Warm the sauce gently on the stove over low heat, stirring occasionally. Avoid boiling rapidly to keep the flavor bright and the texture smooth.

Common Questions Answered

• Can I can or preserve this sauce? Yes, you can safely preserve it using the water bath method. Just be sure your jars stay covered with at least 2 inches of water, and boil them for 15 minutes. Follow tested canning instructions that are specific to your elevation for best results—see these detailed water-bath canning instructions for a step-by-step reference.
• Can I make the sauce spicier? Totally! Feel free to add more cayenne, hot sauce, chopped fresh chiles, or smoked chipotle powder to spice things up to your taste.
• What if my sauce doesn’t thicken enough? Just keep simmering it uncovered until it reaches the thickness you want. Sometimes it takes a bit longer depending on your stove and the moisture in your rhubarb.
• Can I use frozen rhubarb? Yes! Just thaw frozen rhubarb and drain any extra water before roasting or cooking. You may want to reduce added water in the recipe since frozen rhubarb can be juicier.
• Is this sauce vegan? Yes, all the ingredients here are plant-based. If you’re strictly vegan, double-check your Worcestershire sauce brand, as some contain anchovies.
• How long does it keep refrigerated? About a month in an airtight container—plenty of time to enjoy it on your favorite grilled dishes!