There are a bunch of Taiwanese restaurants in the San Mateo/Foster City area, but Spices stands out for having a nice interior and a full page of vegetarian (mostly vegan) options. In fact, the menu even uses the word vegan, which is a rarity in traditional Taiwanese restaurants.
We got the "numbing spicy cucumber" ($5.50), stir-fried watercress ($10), fire popped tofu skins ($10), and a "stinky fried tofu" ($6), the latter of which gives this restaurant some fame, as it's an unusual dish.
First, the stinky tofu is exactly what the name implies. The smell isn't unbearable, but it's not pleasant---it's hard to describe. The taste of the tofu, which is fried, is also bizarre and strange. I'm an adventurous eater, but I found this dish basically unpalatable after a couple of bites, and my Chinese friend (who grew up eating this type of dish) also admitted that she can only handle stinky tofu in miniscule quantities. That said, I could understand the appeal---it tastes weirdly sour and made my jaw twitch. Maybe if I ate it many more times it would grow on me. Or not.
The numbing spicy cucumber didn't have enough Szechuan peppercorn, so it didn't numb very much. The dish comes cold, so it's oddly unsatisfying and not particularly spicy either.
The fire popped tofu skins were not in fact tofu skins; they seemed to me more like thinly-sliced pieces of dense tofu. The sauce on this dish was okay, but again not spicy enough and the dish felt kind of drab; it basically was just strands of tofu with a few slivers of greens.
Oddly enough, the watercress ended up being the best dish. It was a simply saute of watercress with garlic and tasted great.
The portion sizes are good, so this place is a decent value. Unfortunately, they don't have brown rice, so I went without.
The service was friendly and prompt. They even removed the stinky tofu from our bill as neither of us liked it. I appreciated this mightily.
All in all, I'd probably return to Spices as the menu shows promise, if they could just jack up the spice a little.