So, what's the big deal about this beef anyways? What does it taste like?
How does Wagyu beef taste? If it's cooked wrong, lousy. Bland. Not too flavorful. Kind of boring. If you cook it right? Awesome. Beef foie gras. Smooth, velvety, incomparably sweet with a subtle tang of savor that lingers on the palate like a rare perfume. It's a Japanese thang, I guess, and a Westerner used to eating a huge plate of aged beef (which is also something I adore) might not be able to fully appreciate the subtlety of Wagyu.
And true Kobe beef? Overrated. At ten times the price because the cow was raised on expensive land eating expensive Japanese grain and beer, the quality is not noticeably better than ordinary Wagyu beef that grades out to super-prime. About those legendary cow massages? It's in part because they don't have enough room to exercise in a normal paddock. American and Australian raised Wagyu cattle that get the oleaginous feed and a well designed exercise program grade out just fine, and I doubt even the most discerning palate could tell the difference if the grade was the same.
How do I cook Wagyu if I actually buy some?
"If you try to treat a Wagyu steak as if you were cooking beef, you will be sorry you did, and you will look down at your plate and say, "****, I spent that much money on
this?" Don't do that. Think about quick-sear cooking techniques for things like rare tuna and foie gras, not about steak. If you do it right, you may just acquire an addiction for life.
Open flames, preheated cast iron and Wagyu beef are friends. Good friends. A quick sear of thin pieces in a very hot flame works wonders, and if you are lucky enough to have a thick steak, you want it absolutely seared and crispy on the outside and raw and quivering on the inside, even if you do not normally eat your steak this way.
You can use an intensely preheated cast iron pan or grill to achieve this effect, but you cannot allow the steak to remain in contact with heat for long enough to melt all the fat and cause it to drip out of the internal structures of the meat, or you will end up with boringly tough, dry, expensive meat.
Wagyu is a fragile creature under heat. Treat it delicately and with the utmost care, and it will reward you with velvety perfection. Another good analogy to cooking Wagyu is that of a baked Alaska—you need to sear the outside, but if you let it sit under the heat too long, it will melt the ice cream inside, and you will have an unappetizing mess. The physical structure of Wagyu beef is not unlike ice cream in that it can literally melt and change into something very different from its ideal form."
http://members.tripod.com/~BayGourmet/wagyu.html