We tried mashed potatoes from six different fast-food restaurants.

We tried Popeyes, El Pollo Loco, Culver’s, Church's Chicken, KFC, and Boston Market.

The winner was Boston Market.

Nothing is quite as comforting as a cup of mashed potatoes and gravy, but some fast-food chains make it better than others.

To get to the bottom of which is best, we tried mashed potato sides from six fast-food chains. Each restaurant we tried was ranked in Restaurant Business's top-100 chain restaurants of 2017.

Here's what we tried:

Popeyes

El Pollo Loco

Culver’s

Church's Chicken

KFC

Boston Market

For consistency's sake, we ordered the smallest option at every restaurant (called "small," "individual," or "regular") and tried the potatoes and gravy separately and together to grade both parts.

Here's how they measured up.

Popeyes had one of the cheapest potato dishes

Popeyes mashed potatoes and gravy are some of the cheapest. Martha Sorren

A "regular" size of mashed potatoes and gravy was $1.99. But you pretty much just got one scoop of potatoes for that, and the least amount of gravy from all the places we visited.

The gravy was spicy

The gravy from Popeyes was surprisingly spicy. Martha Sorren

If you're looking for traditional mashed potatoes you might want to skip Popeyes, since it breaks the mold with its Cajun gravy. It's not that the flavor was bad; it was just unexpected. The potatoes themselves tasted pretty plain, but the spice from the gravy did amp that up.

El Pollo Loco had the most expensive mashed potatoes

The mashed potatoes from El Pollo Loco were the most expensive option. Martha Sorren

The chicken chain sold its "small" side of potatoes and gravy for $2.99. Despite the high price, the flavor made this one of the better options on this list.

The potatoes were fluffy and nicely seasoned

El Pollo Loco potatoes and gravy were perfectly seasoned. Martha Sorren

You could probably even eat the potatoes without gravy — they held their own. The gravy, which was much thicker than the other restaurants', added extra richness to the potatoes. But it was quite salty, so if that's not your thing, be warned.

Culver's makes gluey potatoes

Culver mashed potatoes were gluey and the gravy smelled like beef ramen. Martha Sorren

Culver's isn't known for its potatoes. Their "regular" size was $2.19 and pretty large, but the potatoes were thick and gluey. The gravy helped thin them out a bit, but didn't smell like traditional gravy.

The Church's Chicken gravy was not what I expected

The Church's gravy had an unexpected taste. Martha Sorren

The "regular" size was $1.99 for a large scoop of thick mashed potatoes and gravy.

The gravy tasted tangy and almost sweet — like with Popeyes' Cajun gravy, if you're not expecting a different flavor profile, it takes you by surprise.

But unlike spicy gravy, which your tongue can eventually understand, the tangy flavor profile of this gravy was a little overwhelming.

The KFC price was the second cheapest

KFC's mashed potatoes were only $2.09 for an individual portion. Martha Sorren

They were only $0.07 more than the most inexpensive potatoes, ringing in at $2.09 for an "individual" portion.

It delivered on your standard mashed potatoes

KFC mashed potatoes are classic. Martha Sorren

The smooth, thin potatoes and gravy tasted almost like what your grandma would serve at Thanksgiving. They lacked the lumpiness of real, homemade potatoes, but they'll hit your nostalgia spot straight-on.

Boston Market tasted like it uses real potatoes

Boston Market uses real potatoes. Martha Sorren

While some of these other restaurants' potatoes tasted fake or instant, Boston Market's tasted like they used real potatoes. They were fluffy and just the right amount of lumpy, which made the $2.59 "regular" size pretty hearty.

The spices added an extra kick

The gravy has the right amount of spice. Martha Sorren

The potatoes were seasoned liberally with pepper, but the gravy was a little milder — perhaps to keep from overwhelming your palate. You could add extra salt if you wanted yours to have a little more flavor.

The winner is…

Boston Market mashed potatoes are the best. Martha Sorren

Boston Market's mashed potatoes tasted the best and the most real. If you're looking for a homemade-potatoes feel, it doesn't get better than this restaurant chain.

It doesn't hurt that when you eat in-store they give you real bowls and silverware. It's like eating at home, even when you're out.

Honorable mentions go to KFC, Popeyes, and El Pollo Loco

KFC, Popeyes, and El Pollo Loco all get an honorable mention. Martha Sorren

But since Boston Market is a little pricier, if you're looking for a more inexpensive treat, you might want to try KFC.

And if you're looking to break out of the flavor mold, try Popeyes' spicy gravy or El Pollo Loco's thick and salty gravy. You can never have too many potatoes.

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