I've been coming back to his restaurant on and off for over 10 years. They've moved a few times, but now they're back on 2 floors at their original location at Siam soi 4.
It's not very atmospheric, but the food is always delicious, and during the day the place is very popular with locals and tourists alike. My favourites are the tom yam noodles (spicy and sweet) and yam ponlamai, a spicy fruit salad, nowadays served in a cabbage leaf, and I always drink their chrysanthemum drink, a sweet yellow drink made of flowers. With friends I've shared some other dishes like po pia sod (spring rolls) and they were good too. Prices are reasonable.
Service is friendly and quick. They have an English menu, but don't speak much English.