Last spring, the skies over New York City parted, and two perfect angels descended from heaven with a delicious treat that would forever change mankind's relationship to pastries: The Cronut.

Five months, hundreds of blog posts, and who-knows-how-many Cronuts later, we are reminded that for every profit there are false profits, and the Cronut already has at least one — Starbucks' Duffin.

As the name suggests, the Duffin is a half-donut, half-muffin pastry, made with a buttermilk-nutmeg batter, and filled with jelly. According to Vanessa Wong at Businessweek, it "tastes like a moist, cakey muffin."

Sounds yummy, right? Starbucks seems confident that it will win converts — the item launched in 730 U.K. stores last week, not as a test run, but as a permanent menu item, alongside classics like the Iced Lemon Pound Cake and Old-Fashioned Glazed Donut.

Why are they so sure it will succeed? "The Duffin follows a recent fusion trend of combining two bakery items into one hybrid," Ian Cranna, vice president of marketing & category for Starbucks U.K. told Wong.

It's true, though the fad is in no way restricted to pastries. Ever since Doritos Locos Tacos became a smash hit, with over one million sold in their first year, it seems like every week blogs and tweeters get stoked on a new combo item — everything from the Cronut to the Cheeseburger Stuffed-Crust Pizza.

But the Duffin already has two intrinsic problems that may turn off customers.

On its website, Starbucks says, "Inspired by our muffins, we sat together with our bakers and pondered how you could make a muffin go one step further." But some are saying Starbucks found inspiration in OPM — Other People's Muffins — as well.

Duffins have already been around for years — specifically at Bea's of Bloomsbury, a bakery with four locations in London. Bea's wrote on its Facebook page:

I understand that Starbucks U.K. wants to cash in on this hybrid dessert craze — I get that. But to make a product that uniquely contains buttermilk, nutmeg, and raspberry jam, and to have the name duffin, not doughnut muffin, and to have claimed that their team of 'bakers' came up with it magically on their own, seems a bit odd to me, particularly when the British baking lexicon isn't heavy on nutmeg or buttermilk. [Eater]

Starbucks' Cranna even told Wong, "Since launching the Starbucks Duffin we have discovered that there are lots of other Duffins out there."

The second potential problem is that food bloggers seem unimpressed. It's "just a muffin with some jelly in it," says Paula Forbes in Eater.

Dominique Zamora at Foodbeast feels the same way: "Is it donut-shaped? No. Deep fried? Not a chance. Seriously, it’s just a jelly-filled muffin."

Zamora goes on to sum up both problems: "[I]t does combine, in no uncertain ratios, features of one breakfast pastry with another. Really though, it’s a sham. An entirely opportunistic, corporate sham."