Bangkok Center Grocery
You'll miss the Bangkok Center Grocery if you're not paying attention; Mosco Street is tucked into the south side of Chinatown, and but a half-block long.
Palm sugar is one of five pantry staples Yoottapong insists one should have on hand at all times in order to make great Thai food.
Bangkok Center Grocery carries several forms of tamarind, including fresh paste (with seeds—be prepared to deal with stickiness!), liquid tamarind concentrate, and (not pictured) pickled tamarind leaves.
Thai basil, a hard-to-find cousin of the widely available sweet or Italian basil, is a key flavor in many Thai dishes. Yoottapong also carries the fragrant and much loved Holy basil.
Curry by the canful
Although the best curry is, according to Yoottapong, the kind you'll find fresh in his refrigerated section, Bangkok Center Grocery also carries every kind of canned and boxed curry imaginable, including the celebrated Maesri and Mae Ploy brands.
The small store is closely packed with ingredients, and it's easy to miss small treats among the more obvious offerings. If you spend some time eying the shelves, you'll come across things like quail eggs and coconut meat in syrup.
Yoottapong also carries a few non edible Thai products, such as these tiny plastic tubs of lime paste (mysteriously labeled "for ceremony use only.")
For a bit of light reading with your homemade Pad Thai, at Bangkok Center Grocery you'll find a selection of Thai-language magazines and newspapers.
As you check out be sure to grab a box of spicy tamarind candies, or these sweet star gooseberry jellies, both classic Thai sweets.