How to Thicken BBQ Sauce: 4 Simple Hacks

Annabelle – An experienced food writer and editor. She focuses on common sense, easy to replicate recipes formulated to help keep things fresh and exciting while fitting into her day to day life as a wife and mother.

Producing a homemade BBQ sauce with an ideal consistency can be a real challenge. The excess water from your chopped tomatoes can mix with the vinegar and olive oil to create a runny, diluted liquid that looks nothing like how it does in your recipe book. 

4 Ways to Thicken Your BBQ Sauce


There are several methods for how to thicken BBQ sauce, from simmering the liquid over a moderate temperature to adding a thickening agent like cornstarch. Here are four of our favorites:

1. Reduce the sauce over heat

The simplest and most effective way to thicken your barbecue sauce is to reduce it by keeping it over low heat for 30 minutes to an hour. Get rid of any remaining solid clumps of food in the saucepan before you reduce the liquid. For instance, if there’s a large lump of tomato or a sizable wedge of onion floating around in the sauce, scoop it out. Leaving these chunks in the sauce slows down the reduction process.  

To reduce the liquid properly, turn the heat up to bring the sauce to its boiling point. When the liquid starts bubbling, turn the temperature back down to a low-to-moderate heat, then leave the saucepan uncovered for at least 30 minutes. If you want to speed up the process, use a skillet or pan with a wide base, so more of the sauce is in direct contact with the heat.  

During this period, the sauce will simmer lightly, and diluting liquids like water or stock turn into vapor, evaporating into the surrounding air. This results in a thicker, more flavorful BBQ sauce.

2. Add starches like flour and cornstarch to the sauce

When you add starch to any diluted sauce, the carbohydrate granules react with the heat to expand. As they grow, these tiny grains attract and capture the water molecules diluting the sauce, creating a thicker liquid. 

Common flavorless starches like flour are effective because they help to thicken your liquid without detracting from the taste. Before you add flour to your BBQ sauce, mix it with a dash of cold water in a small bowl. This separates the starch grains and stops them from sticking together and floating around in your sauce. For every 2 tablespoons of flour, use ¼ cup of water, and whisk well. 

Heat your barbecue sauce until it’s simmering, then add the smooth and lightly diluted flour solution. Stir all the ingredients together and let the liquid simmer for a few minutes, continuously checking the consistency. 

If you don’t have any flour, add cornstarch to the sauce. Make a cornstarch thickening solution by mixing it with cold water. In this case, use a ratio of 1 tablespoon of starch to 1 tablespoon of water. It’s important to remember that 1 tablespoon of cornstarch thickens twice as much liquid as 1 tablespoon of flour, so you won’t need to add as much of it to your sauce.

3. Add food gums to the sauce

When you think about how to thicken BBQ sauce, you might not consider using a food gum. However, natural additives like xanthan and guar are effective thickening agents. Xanthan is a polysaccharide that comes from fermented sugars, while guar is a combination of 2 sugar types extracted from guar beans. 

When you use xanthan gum to thicken your barbecue sauce, only add ¼ teaspoon at a time. This additive works quickly, so you don’t want to add too much right away and create a lumpy liquid. 

If you’re using guar gum as an alternative thickening agent to flour, divide the amount of flour you would typically use by 16 to get a suitable value of guar. If you’re adding guar gum rather than cornstarch to your liquid, divide the amount of cornstarch you’d normally use by 8. Adding too much guar powder at once can lead to clumping in your sauce, so make sure you’re getting these measurements right.

4. Add fats like butter to the sauce

You can create a roux or Beurre Manié mixture and add this to your sauce to thicken it and improve its flavor. To make an effective roux, use equal parts fat and flour. Melt 1 tablespoon of butter in a saucepan, measure 2 tablespoons of flour and sieve it into the pan. Use a wooden spoon to slowly stir together the flour and fat for several minutes, keeping the burner at a medium-to-high heat. 

After 3 or 4 minutes, the liquid should start to thicken and turn into a roux. When you’re satisfied with the consistency, pour the roux into your barbecue sauce. The roux’s starch granules swell up and absorb the diluting agents in your sauce, thickening the liquid. 

You make a Beurre Manié by kneading together softened butter and an equal amount of flour in a bowl. A typical ratio is 1 tablespoon of butter to 1 tablespoon of flour, although you can vary this based on the amount of sauce you’re thickening. After you’ve produced a dough-like substance, cut it up into little chunks and add these pieces to your barbecue sauce.

A Sauce Thickening Hack Helps You Serve the Perfect BBQ

Aside from knowing how to make a great BBQ sauce, learning how to thicken any sauce is a crucial skill for anyone, from top-level chefs to those who are cooking for friends and family in the comfort of their own kitchen.

A diluted and watery barbecue sauce can taste flavorless and ruin the spiciness of everything else on your plate, but there are a few easy fixes. You can reduce the liquid over a moderate temperature, add various starches to the sauce, or create a roux and use it to thicken your BBQ sauce for the perfect consistency every time!