The One Extra Add In You Need To Add To Your Five Guys Milkshakes

The fast food chain Five Guys is known for their fresh, never-frozen burgers, their genuinely delicious fries, and a robust secret menu, thanks to their abundance of free toppings. But it turns out that one of the best secret menu items at the chain has to do with an unusual add-in for their milkshakes, instead of one of their savory items. 

Five Guys started selling milkshakes in 2014 (via Eater), serving up a standard vanilla "handspun" milkshake (meaning the shakes are mixed by hand, not poured out of a machine) and 10 free mix-ins diners could add in (via Igor International). Surprisingly (for a fast food chain, at least), Five Guys milkshakes are made with a fairly small ingredient list (via Five Guys). The four main ingredients are milk, nonfat milk, sugar, and whey, with less than 1 percent of the ingredients consisting of thickeners, preservatives, and natural flavorings. 

But you can make that simple vanilla milkshake into something really extraordinary with the mix-in options, and it turns out the best add-in is also the one that you might find the most surprising. 

Five Guys offers 10 different mix-ins for their vanilla milkshakes (via Five Guys). Most of them are typical of an ice cream shop offering: bananas, cherries, chocolate, coffee, malted milk, Oreo pieces, peanut butter, salted caramel, and strawberries. Any of those add a hit of flavor and sweetness to your shake. 

But the most interesting item on their mix-ins menu is something savory: bacon. 

That's right! You can add crumbled, applewood-smoked bacon to your Five Guys milkshake to put a sweet and salty twist on your ice cream treat (via Washington Business Journal). 

While a bacon vanilla milkshake sounds fine, you can make even more elaborate treats by combining the mix-ins. 

Make an Elvis-inspired shake (via Allrecipes) by combining bacon, banana, and peanut butter, or maximize the sweet and salty with a salted caramel bacon shake. 

All told, there are more than 40,000 different flavor combinations (via WebMath) you can make with Five Guys' 10 different mix-ins, but we can't guarantee that all of them will taste good (there's something about a bacon cherry coffee milkshake that doesn't exactly sound delicious). 

Bacon often costs extra when adding it to sandwiches at restaurants, so it made us wonder — how much does it cost to add bacon to a milkshake at Five Guys? The answer was surprising. 

When it comes to burgers, Five Guys has a lot of free topping choices — mayo, lettuce, pickles, tomatoes, grilled onions, grilled mushrooms, ketchup, mustard, relish, onions, jalapeño peppers, green peppers, bar-b-que sauce, hot sauce, or A1 sauce — but their bacon burgers do cost more than a regular hamburger (via Fast Food Menu Prices). We thought that would mean that adding bacon to your milkshake would cost extra too, but it turns out, we were wrong.

It's a different story when you're ordering a milkshake. At Five Guys, all of the milkshake mix-ins, including the applewood smoked bacon, are free. 

Free bacon in a milkshake is hard to pass up, especially when you can combine it with nine other tasty mix-ins to boot. 

Bacon may contain protein, but it doesn't exactly have a reputation for being healthy. In fact, some doctors even warn that processed meats like bacon could cause cancer. 

That major health scare aside, putting bacon in your milkshake also bumps up the calorie count. 

A plain Five Guys milkshake contains 670 calories, 32 grams of fat, and 360 milligrams of sodium. Adding bacon, of course, ups those numbers (via Five Guys). 

While bacon only adds 80 calories to your shake, it also adds 7 grams of fat and 260 milligrams of sodium. 

That means that one bacon milkshake from Five Guys contains 750 calories, 39 grams of fat, and 620 milligrams of sodium. And that's without whipped cream!

For someone eating 2,000 calories a day, the daily reference intake (DRI) of fat in their diet should be 44 to 77 grams of fat a day (via Cleveland Clinic). At 39 grams of fat, a Five Guys bacon milkshake puts you well on your way to maxing out the daily threshold of fat intake, and it doesn't include any "healthy" fats, like those that come from avocados, olive oil, and salmon.

Even worse? You're only supposed to eat 22 grams of saturated fat each day, but a Five Guys bacon milkshake contains a whopping 24 grams. 

This doesn't mean that you should never indulge in the salty-sweet frozen pleasure of a Five Guys bacon milkshake, but it's definitely a treat to be enjoyed in moderation.