Bacon milkshake? Yes, from Jack in the Box.

Bacon milkshake is available for a limited time as part of from Jack in the Box's new 'marry bacon' ad campaign. Bacon milkshake doesn't appear on the menu. You have to ask for it.

If conventional wisdom says that bacon makes everything better, then Jack in the Box may finally have discovered the exception: the bacon milkshake.

"It's for real. Bacon Shake," reads an ad from the San Diego-based fast food burger chain. "Ask for it today."

The public reaction so far has been largely negative, but taste isn’t really the point. The bacon shake is the latest in a long line of fast food fare so outrageous that they serve mainly to draw attention to the fast food chain as a whole, rather than as a serious menu item. Take KFC’s “Double Down” sandwich from 2010 (the one with fried chicken breasts as the “bread”), or the perennial resurgence of the McDonald’s McRib.

The latest porky dairy treat is a part of Jack in the Box’s new ad campaign, which asks the question: If you like bacon so much, why don’t you marry it?

The bacon milkshake may actually be the least disturbing part of the campaign: A trip to the restaurant’s marrybacon.com website will treat you to a video of a guy literally marrying a bacon cheeseburger. While there, you can also “make your own bacon baby” – upload a headshot of yourself, and your facial features will be superimposed onto a strip of bacon which will then be added to a baby’s body. (If it sounds icky, that’s because it is).

But back to everything you need to know about the bacon milkshake. It’s as indulgent as you would expect a bacon milkshake to be: the regular, 16-ounce size has 773 calories, 40 grams of fat, and 75 grams of sugar. The 24-ounce size has 54 grams of fat and 1,081 calories (to put that in perspective, the recommended daily caloric intake for an average-size woman is 2,000 calories). If you’re keeping kosher or vegetarian, you’re in luck: The shake is made with bacon-flavored syrup, rather than the genuine article.

It’s available for a time “as limited as limited can be,” at participating locations. Jack in the Box has 2,100 stores in 19 states, mostly in the western half of the United States. The shake doesn’t appear on the menu; you have to ask for it.

How does it taste? Plenty of brave bacon-shake tasters have weighed in around the Web:

“Wow. That was horrific, ” wrote Brock Keeling, a blogger for SFist. “Bad it was. Aggressively so, A heavy, lingering bland with a touch of smoke that doesn't go away. Jack in the Box's Bacon Shake hits the senses like smokey maple syrup.”

Noting a lack of true bacon flavor, Edwin Goei at the OC Weekly calls the shake “less a marriage to bacon than a harmless flirtation”

“It’s like I’m 90 years old and I have to drink my food,” said a man taste-testing the shake on film for CNBC’s Jane Wells in a California mall.

Food items like the bacon milkshake are fun in theory, and they get their purveyors into the news for a few days. But in all likelihood, very few people are actually buying a Double Down or the McRib for lunch on a regular basis.

Nor is bacon in dessert anything new. Last year, Denny’s introduced a “Maple Bacon Sundae” as part of its “Baconalia” festival; unlike the Jack in the Box shake, it came topped with real bacon. Chocolate candy bars with bacon bits have become an increasingly common sight in many grocery stores, including Whole Foods. A quick Google search unearths scores of recipes for homemade bacon milkshakes, most of them involving maple syrup, ice cream and, well, bacon.

Still, if curiosity gets the best of you, visit jackinthebox.com and type your Zip Code into the store locator to find a Jack in the Box near you.