How To Reheat Leftover French Fries To Crispy Perfection

You’ll never leave those delicious diner leftovers behind again.

by
French fries in basket with newspaper lining.

French fries. Photo, Roberto Caruso.

This scenario might sound familiar: You’ve just finished a meal at your favourite comfort food spot. Remaining on your plate are the bulk of the thin-cut, twice-fried, beautifully crispy fries you can never find enough room for. You may hate food waste, but you don’t stop the server from taking your plate away because you recognize a simple truth: leftover french fries are not delicious—they quickly become soggy, gritty and dry.

The good news: There’s a simple trick for reviving leftover french fries that even a kitchen amateur can tackle. The bad news: Once you learn this trick, you’ll realize how many good fries you’ve wasted in your life.

Why save your leftover french fries?

The truth is, leftover fries aren’t actually bad—they’re just misunderstood.

When restaurant french fries arrive at your table nice and hot, they’re delicious because (among many reasons) of a little thing called starch. All potatoes have starch. When fries are cooked at a very high temperature, the starches in them are hydrated (moisture goes in), puffing them up and helping the outer skin get nice and crisp. When these same fries cool, the starches secrete moisture, which makes its way to the fries’ crust, leaving them soggy and limp. The secret to saving those fries: heat them up again—with a few extra steps.

How to reheat your fries, properly


Roughly chop your leftover fries into two-inch pieces (this ensures maximum crispiness). Once you’ve got them all about the same size, heat a few tablespoons of vegetable oil to medium-high in a heavy-bottom pan (cast iron is best for even heat distribution). When the oil is hot, place the fries in the pan and cook them for about five to ten minutes, stirring often, until you can see the fries start to crisp up again. When they’re done, move them to a paper-towel-lined plate to remove any excess oil, season if needed, and serve immediately.

Make a meal of your leftovers

In order to make a proper meal (or even a decent-sized side dish) out of them, you need a fair amount to work with, so it’s best to ask for those fries to-go when you have about a baseball-sized amount or more. You can freeze the fries when you get home (I put them in a Ziploc bag first) and just defrost the day of—freezing doesn’t affect the taste.

Here’s one of my favourite ways to revive those fries: Cook up some minced garlic and diced onions until soft, then add the chopped-up fries to the pan and cook until they’re crispy. Sometimes I put in a few cubes of cheese (cheddar or mozzarella) until melted, then top with an over-easy fried egg or two, and some diced green onions. It’s a great kitchen-sink dish to start the weekend (and not bad for fighting a hangover, either).

Originally published June 2018; Updated May 2019.