Jingiskan? Lamb don? Mutton don? What's in a name when it tastes this good?

A friend took me to this pint-sized place in Tokyo the other day for some jingiskan (Genghis Khan); a dish of grilled mutton (aka adult lamb).  Actually, with jingiskan you're often going DIY with that using a hot plate at your table.  On this occasion my grilled mutton came prepared on a bowl of rice.  Can I call this 'mutton don'?

Now, gyūdon (牛丼 - beef bowl) has become something of a staple for me in Japan.  It's cheap, quick and seldom fails to deliver the goods, even at 'fast-food' joints like Matsuya and Yoshinoya.  This was my first time to try 'lamb don', and my first time to pay 1,200 yen for a bowl of meat on rice in Japan.

I'm not sure any dish that basically lumps meat on rice could ever be worth 1,200 yen, but if there's one that comes close, it could well be this one.  

Where a serving gyūdon often has meat that is kind of stringy and flimsy, the cuts of meat in this dish were a class above.  Really substantial, juicy, and with a little bit of 'chew' factor, too.  The raw egg in the middle might have been something of a hurdle a while ago, but spend long enough in Japan and you get used to it.  The dish was topped with some diced negi and served with a steaming cup of green tea.

We ate in one of those places you can often find in Japan that get by with only one or two dishes on the menu.  Popular joints, like this, also have a limit on the number of dishes they can make, and they usually sell out.  Pretty quickly.  We arrived at around 1:00 pm at the (by then) empty shop and were served the last two dishes available.