The best Thai curries aren’t a one-night-stand of flavor, however wild; they’re fulfilling and lasting and a wow, for the moment and for awhile. Zen Yai (425 State Street, 957-1193) makes a Panang Curry one could consider marrying. Your taste buds can practically count the coconut milk, lemongrass, and fish sauce molecules as they backstroke-in tandem-on by. But it’s the richness of the sauce that makes this Panang so pleasing. What’s more, the meat (while beef’s standard, try it with pork) can remain so tender even in your to-go cup. Sure, there could be more of it, but when it leaves you wanting, it’s done its job. Still, you will wish for a bigger serving.