To begin, the Wagyu flights at BLT Steak are a thing you should try if you are fancy and/or rich. With that out of the way, the downtown steakhouse has expanded its Wagyu program, quadrupling its selection of the decadently marbled -- and widely misunderstood -- Japanese beef.

Domestic and imported cuts of Wagyu beef, clockwise from top left: Domestic Wagyu skirt steak with chimichurri sauce; filet mignon; Miyazaki Japanese A5 ribeye; New York strip steak; domestic ribeye. (Maura Judkis/for The Post)

Wagyu comes from four breeds of Japanese cows and can be produced domestically or imported. (Kobe beef, a rarer type of Wagyu, is imported from Kobe, Japan.) If you want to try several cuts and types of the marbled, velvety beef in one sitting, BLT Steak's two Wagyu flights are for you.

A $95 flight focuses on domestic Wagyu, with three three-ounce cuts that include strip, flat iron, rib filet or filet mignon, from farms in Nebraska and Idaho.

Upgrade to the $150 five-cut premium flight, and in addition to the aforementioned, chef Jeremy Shelton will add two two-ounce cuts imported from Japan, both scored A-5, the highest grade for beef. The latter flight is more than enough for two people to split. Both flights come with sides such as pickled ramps, roasted garlic and bone marrow, and a short lesson about the genetics  and provenance of Japanese beef.

So what's the big deal about this particular steak? "Luscious" would be one word to describe it. The fat will melt on your tongue. To beef lovers, it's akin to a very fine foie gras: incredibly rich, both in taste and as a status symbol.

BLT Steak, 1625 I St. NW. 202-689-8999.