Vietnamese/Thai Bethesda area
I've been pretty happy w/ Thai Corner on Bethesda Ave; it's not as good as Ruan Thai or Thai Square (both out in the 'burbs, and widely considered the gold standards for local Thai), but it's not bad at all, especially if you can convince them that you don't want Americanized Thai. (Unless that's what you do want, of course...)
Thai Corner Restaurant
4733 Bethesda Ave, Bethesda, MD
My personal fave for Thai is Nark Kara Thai on Cordell Ave. For Vietnamese, try Green Papaya on Elm St. Can't think of any BBQ in Bethesda, unless you want REAL casual. If so, Chesapeake Chicken and Rockin Ribs on Wisconsin is the place. The only other one I can think of is Rocklands in Glover Park on Wisconsin Ave. It's very good.
I highly recommend you take a 10min drive down Rockville to Ba Le for Vietnamese food. Their Banh Mi, Pho, Spring Rolls, and Entrees are all fantastic and the owner, Christian, couldn't be nicer. It doesnt look like much from the outside but dont let that fool you; it has relatively trendy decor on the inside and they do a lot of business.
The sweet drinks and foods behind the glass counter at the front are also great (their iced coffee is magic)
842-A Rockville Pike
Rockville, MD 20852
Is Ba Le open again? I went a few weeks ago and it was closed for remodeling. I do highly recommend it as well. If you're going up Rockville way I'd also recommend Pho 75 for well, pho.
I'll also second the Green Papaya recommendation on the caveat that the service can be variable. The food's great though, but a little more expensive than you standard "ethnic" restaurant.
Nonsense. There are good Thai and Vietnamese options. For Vietnamese, I would go with Green Papaya. The decor is slightly over-the-top, but the food is always wonderful. For Thai, we like Sweet Basil - very pleasant place with great food - we had a terrific meal there on Thanksgiving! = but I am told that Nark Kara Thai is good, too. I would avoid Tara Thai. I think it is mediocre.
As for pho, well, not so much. The best pho on the MD side of the river is Pho VN 1, up Rte 1 in Beltsville. It is the best pho I've ever had. Magic food. But Bethesda...not really.
Sorry, Axsanb, but there's no really good, let alone California-quality, Thai or Vietnamese (nor BBQ) in the Bethesda area. Plenty of serviceable, mediocre stuff, but I assume you wouldn't bother with that.
If you'll have a car, we can steer you to great Thai (in Wheaton) or Vietnamese (in Falls Church -- or, for Pho, in Rockville or Annandale) elsewhere.
In Bethesda proper, there's nothing extraordinary, except Jaleo on a good night (more often than not, but risky); Passage to India; and decent Peruvian chicken at Chicken on the Run. Faryab is supposed to be good for Afghan (I haven't been).