There's this little place called Cafe Zaiya on 41st between 5th and Madison (not the same place I get my tea). They have a lot of fast Japanese pre-packaged meals, cream puffs from Beard Papa (/drool) and a very lovely bakery section.
In this bakery lies the stealthy mochi doughnut. You might just miss it in between the red bean donuts and the mini pizzas but it's right there waiting for you to take your first addictive bite.
It's covered in granulated sugar and fried to a deep golden brown. Honestly, this doughnut had me at sugar, but there's more!
When you bite into it the texture is quite chewy like a piece of mochi, funny enough. By the time you get to one it's probably absorbed the oil it was fried in so each bite is a sligtly greasy, sugary spackle job on your arteries.
This donut isn't light as air, but it also isn't as dense as its sturdier, bean paste filled counterparts. There are air pockets in between the layers so it reminds me of a french crueller a little (my other doughnut addiction).
I think they pipe them out with a pastry bag/tip to get this perfectly swirled shape. I happened to take a picture of the bottom of this one so you can't really tell.
Some days... oh some days they have them half dipped in chocolate! O_O