The Unexpected Ingredient That Quickly Thickens Pot Roast Gravy

Making a delicious gravy is one of the most important steps in making pot roast, creating that comforting, velvety mouthfeel that reminds us of Grandma's cooking. Traditionally, people use a flour roux or cornstarch slurry to help thicken gravy, with each giving slightly different results from the other. One surprising ingredient, however, may beat both of them, and it's probably something you already have in your cupboard: instant mashed potatoes.

Instant mashed potato flakes are a surprisingly versatile pantry staple, useful for things like a bread crumb substitute, buttery-soft cookies, and some of the best homemade potato chips. Even the legendary Jacques Pépin uses them for his creamy, no-fuss leek and potato soup. These starchy flakes also do a lot of work in thickening soups and stews while adding an extra layer of depth and richness, which is always welcome in a pot roast gravy too.  

Get creative with your gravy by using flavored instant mashed potatoes. Depending on the flavor you choose, the potato flakes add layers of garlic, cheese, bacon, and herbs to the gravy's overall flavor profile. By mixing just a few teaspoons of instant mashed potatoes into your drippings, you can make a thick gravy that fully coats the meat and helps pack each bite with even more of those flavorful pot roast seasonings.

Thickening gravy with potato flakes looks very much like it always does. Deglaze the pan as usual with your preferred liquid. You can strain the fat from the drippings first if you're worried about greasiness, but you don't have to. In fact, collagen-rich cuts like bottom round were Julia Child's favorite meat cut for pot roast precisely because the fat helps both the meat and your gravy develop a deeper, richer flavor.

Transfer the liquid straight to another pot and add extra beef stock if you want to make extra gravy. There's no need for a roux, though the thickening technique works on traditional gravy too. But you do need to bring the liquid to a gentle simmer, just under 200 degrees Fahrenheit, since potato flakes hydrate best with hot water. Sprinkle in 1 or 2 teaspoons of instant mashed potatoes for every 2 cups of liquid. You can grind the instant mashed potatoes finely if you want to make your gravy as smooth as possible, though it should work either way if you stir really well.  

Whisk it for a few seconds, and then let it sit for a couple of minutes (no more than two or three) to thicken. If the gravy hasn't reached your desired thickness, repeat the process until it does, loosening it with a little stock or water if it gets too thick. A little goes a long way with potato flakes. A 2012 agricultural university study out of Thailand showed it can absorb about 7 times its weight in water, so it's best to adjust for thickness in small amounts.