Yesterday my husband and I set a stew going in the crock pot bright and early in the morning. Being bright and early in the morning, I totally forgot about thickening it. I went on line to look for solutions. Plenty of people asked how to thicken a crockpot stew, and yes, there were answers.

• Include a bit of flour (1/4 cup or thereabouts) mixed in at the beginning, possibly tossed with the meat before browning it (assuming you plan to brown it first).
• Leave the lid off and let it cook down. These suggestions were obviously written by people who don’t use slow-cookers and aren’t aware that you don’t use them that way. Keeping the lid on is essential to the ambient heat that builds up and cooks the food. So don’t do this. This is why you don’t normally add as much liquid to slow-cooker recipes in the first place.
• Include mashed potato flakes or at least diced starchy potatoes for thickening.

However, not a single person addressed being able to thicken it at the end. The assumption seemed to be that you really couldn’t do that. Well, that’s all well and good when you remember the flour at the beginning, but when you’re improvising, and you haven’t had your coffee yet, all does not necessarily go as planned.

So here’s what we did, and it not only worked, it worked amazingly well. This was for a stew that occupied more than half of a six-quart crockpot and had a fair amount of liquid; adjust as needed for other amounts.*

About half an hour before the crockpot is due to finish, briefly lift the lid long enough to ladle out roughly two cups of hot liquid; this should leave some liquid remaining in the crock pot. Re-lid. If it isn’t already over high heat, turn it to high heat. (Note that if you have it on a short cycle, such as 4 hours on high heat, you should wait until it’s finished the cycle so you don’t let the heat out early; just turn it back on to high for the extra half-hour.)

Melt four tablespoons of butter in a saucepan over medium heat. Whisk in 1/4 cup of all-purpose flour. Keep whisking as it bubbles, smooths out, and thickens; you want to go for long enough to cook off a bit of the flour taste, but you also don’t want this to get too dark. Maybe a minute, but it’ll depend somewhat on just how hot your burner is. You’re making a roux, and the lighter the roux, the greater the thickening power. So if you see it browning, you’re definitely done.

Gradually whisk in the hot liquid from the stew, and keep whisking until it’s smooth and bubbling. Remove from heat, and stir thoroughly into the contents of the slow cooker. Re-lid and allow to bubble along for another 10-20 minutes.

*For a thick gravy, I find that a ratio of 1:1:1 (butter, flour, hot liquid) works pretty well. If you don’t think you have anywhere close to four cups of hot liquid total in the slow-cooker by the end, adjust the butter/flour amounts downward as well. Or, cook the roux until it darkens somewhat. That will cause it to have less thickening power and will also add a bit of a nutty flavor. You can also make a thinner gravy by adjusting in similar ways.

In case you’re curious, this is what we were making (roughly): First, we drained and rinsed the contents of a can of cannellini beans (white kidney beans)—the 14 oz size. Most similar types of beans would substitute just fine. We spread them out over the bottom of the slow-cooker, then added half of a 28 oz can of fire-roasted crushed tomatoes. We put the slab of meat over that, salted it, and peppered it. We covered it with the rest of the crushed tomatoes, then surrounded it with an assortment of chopped veggies (bell peppers, broccoli, portobello mushroom—that sort of stuff). I spooned maybe a cup of homemade chicken broth overtop, and then we set it on low and let it go for about 9 hours before doing the above thickening routine to it. I think that’s pretty much all of it, although it’s possible I’ve forgotten something.

Goes great with homemade chile-cheese biscuits!

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