The 15 weirdest things fast-food chains ever tried to sell us

KFC isn't one to shy away from over-the-top menu debauchery. But even the most forgiving fans were caught off guard when the chain introduced its deep-fried behemoth, the Double Down, in 2010.

The breadless sandwich used two fried chicken fillets in lieu of traditional buns to hold bacon, cheese, and the Colonel's sauce together. The protein-heavy creation became one of KFC's most talked-about menu items, attracting both morbidly curious food adventurers and revolted food critics.

It sold more than 10 million units in its first month, according to KFC. Stephen Colbert, who sampled one on "The Colbert Report," called it "an edible Hieronymus Bosch painting wrapped in a paper straitjacket."

In 2016, Burger King decided to give America what it really wants: an unholy amount of cheese, deep-fried carbs, and neon-orange snack dust. Mac n' Cheetos was a limited-time snack released by the burger chain through a partnership with Frito-Lay, but it really sounds like a snack created by a preschooler.

The bites came five to an order for $2.49 and featured oozy mac and cheese coated in crunchy Cheetos dust and shaped like a mozzarella stick.

They were supposed to be a portable snack, although eating fried mac and cheese hardly sounds like something that needed to be made more convenient.

Fast-food chains often roll the dice when they want to raise the stakes. And while some of these experiments fail spectacularly, every now and then an oddball slips through the cracks, and you get something called Doritos Locos Tacos.

The Doritos Locos Taco was a hard taco filled with seasoned beef, lettuce, and cheese, but with one major difference. The shell was made from Nacho Cheese Doritos instead of a regular corn tortilla. Taco Bell launched it nationwide in March 2012 after working for nearly three years with Frito-Lay to develop a shell that tasted and felt like an actual Dorito.

Taco Bell sold 100 million Doritos Locos Tacos in its first 10 weeks and passed 1 billion by the end of 2014. Slate even called the Fiery Doritos Locos Taco "a triumph of human ingenuity" in 2013.

The Golden Arches have spent decades trying to expand their horizons, and McSpaghetti was one of their more ambitious detours. McDonald's experimented with pasta in the U.S. during the late 1980s and early 1990s, offering spaghetti with marinara sauce and optional meatballs alongside other Italian-inspired dishes such as fettuccine Alfredo and lasagna.

The experiment struggled to fit into a restaurant built around burgers and fries. McDonald's cited supply and equipment problems when it ended the test in 1992, and the U.S. version eventually disappeared from most menus. In the Philippines, however, McSpaghetti found an audience. Introduced there in 1986, it features a sweeter sauce (often studded with sliced hot dogs) and remains a popular menu item, often served alongside fried chicken.

When a bouquet of flowers just doesn't cut it, the answer is a fried chicken drumstick. In 2014, KFC teamed up with Louisville florist Nanz & Kraft to create a chicken corsage for prom season.

The $20 arrangement was designed to hold a drumstick on a bed of baby's breath, and each one came with a $5 KFC gift card so buyers could pick up a fresh piece of chicken (Original Recipe or Extra Crispy) before the big night.

Local buyers got fresh flowers, while out-of-town orders came with silk, and only 100 were up for grabs.

Borrowing a page from the state fair playbook, Long John Silver's tested a deep-fried Twinkie in Pittsburgh and St. Louis in 2017 before rolling it out nationwide for a limited time. The vanilla cream-filled sponge cake was lightly battered and deep-fried, selling for 99 cents each or $1.89 for two.

Of all the gimmicky combinations, bacon is probably the most overused ingredient, dragged into pairings that have no business including it. In 2012, Jack in the Box introduced a bacon milkshake, made with vanilla ice cream and bacon-flavored syrup (no actual bacon involved). The limited-time shake wasn't listed on the menu; it was a "secret item" as part of the chain's "Marry Bacon" campaign.

Stuffed crust on a pizza is one thing. Ringing a pizza with mini hot dogs is another level of overdoing it. After serving versions with hot dogs baked into the crust in the U.K., Australia, Thailand, Canada, and the Middle East, Pizza Hut brought the idea stateside as Hot Dog Bites Pizza in June 2015. The large pizza came with 28 mini hot dogs baked into the crust, plus a side of French's mustard for dipping. It cost $11.99 and was available while supplies lasted, which was probably for the best.

Carl's Jr. launched its Most American Thickburger on May 20, 2015, topping a one-third-pound beef patty with a split hot dog, American cheese, and Lay's Kettle Cooked potato chips. It was an entire Fourth of July cookout squeezed between two buns, with 1,030 calories to show for it.

The Waffle Taco was part of Taco Bell's first national breakfast menu. Launched nationwide on March 27, 2014, it replaced the traditional taco shell with a folded waffle filled with scrambled eggs, cheese, and a choice of sausage or bacon. Syrup came on the side. It didn't survive for long, disappearing from menus in 2015.

Cinnabon, a chain known for cinnamon rolls the size of small tires, took a detour into savory territory in 2012 with the Pizzabon. Tested at its Cumberland Mall location in the Atlanta area, it swapped cinnamon and frosting for marinara sauce, melted cheese, and pepperoni, all baked into Cinnabon's signature rolled dough.

Dunkin' Donuts once experimented with putting a savory breakfast sandwich between two halves of a glazed donut. Tested in eastern Massachusetts in April 2013, the Glazed Donut Breakfast Sandwich went nationwide on June 7, 2013 (National Donut Day), featuring a fried egg and cherrywood-smoked bacon. At 360 calories, it was technically lighter than some of the chain's more conventional breakfast sandwiches.

When McDonald's entered the pizza business in the late 1980s, it wasn't settling for a slice on the side. The chain tested a full-size, traditional pizza in 1989 and expanded the experiment to more than 500 locations by 1991. But there was one problem. The pizza took around 11 minutes to cook, which is an eternity at a chain built on speed. McPizza eventually disappeared from nearly every menu, with the last two holdout locations in Pomeroy, Ohio, and Spencer, West Virginia, selling their final pies in 2017.

In 2012, Pizza Hut introduced the Crown Crust Burger Pizza in the Middle East, surrounding the pizza with tiny cheeseburger bites tucked into the crust. The center was topped with beef, iceberg lettuce, tomatoes, melted cheese, and special sauce, turning the whole thing into a pizza, burger, and taco salad having an argument on the same plate. The pizza was available in 12 countries across the region, but U.S. customers were left to admire it from a safe distance.

McDonald's once tried to convince America that a slice of grilled pineapple and melted cheese on a bun was a good idea. Ray Kroc created the Hula Burger as a meat-free option for Catholic customers avoiding meat on Fridays during Lent. But Cincinnati franchisee Lou Groen had a competing idea: a fish sandwich he'd developed to win back his Friday customers. Kroc wasn't convinced the Filet-O-Fish would be a hit, so he decided to put his own bizarre creation to the test against it.

The two sandwiches went head-to-head in a sales competition on Good Friday 1962, and the Hula Burger was absolutely demolished. The Filet-O-Fish sold 350 orders, while the pineapple-and-cheese monstrosity managed just six. The Hula Burger was quickly discontinued, while the Filet-O-Fish became a permanent menu item in 1965.

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