The pastry case might be stocked with pie-like wedges of taro mashed and whipped like potatoes and transformed into a confoundingly light custard. Tiny pastel rice-flour cakes suggest coins in a fairy kingdom, dimpled at the center and haunted by jasmine. Steamed puddings of coconut cream, with no meddling but salt, rest atop delicate translucent bases of rice flour, palm sugar, coconut milk and pandan — a flavor so difficult to pin down, I can offer little more than to say that it always makes me picture bamboo slicked with rain.
A coconut custard reveals a buried treasure of corn and tapioca pearls. Shortbread, a borrowing from the West, is utterly estranged from its origins by a fragrance that infiltrates and possesses the dough: Mr. Kosalanan smokes the flour first, over a scented candle. Luk chup are a sly improvement on marzipan, made of mung-bean paste, with a subdued mustiness and notable restraint in sugar; pieces are sculpted into cherry tomatoes, miniature peaches and alarmingly realistic chile peppers, Corvette-red with a high gloss.
These are desserts that favor surprise and evanescence over sweetness. Sometimes they’re not even as sweet as the savory dishes that make up the brief menu. Sugar seems to have found its way into turmeric-stained crepes, fried into a crispy sleeve for ground chicken, shrimp and tofu interlaced with shredded coconut and pickled radish; a half-pancake, half-omelet with briny pops of mussels, slapped over a hash of bean sprouts; and bronzed nubbly corn fritters with whole kernels caught in a mesh of batter.
Occasional streaks of heat, as in maeng pla, flaked mackerel strewn with roasted peanuts and tucked into lettuce, are a relief. But these are snacks, after all, not meant to be eaten en masse or to compose a meal. I would have been happy with just curry puffs, neatly pleated and radiating warmth, and rice noodle rolls, akin to Chinese cheung fun: floppy, chewy bands of rice-flour dough loosely wrapped around a nicely salty filling of chicken, tofu and shiitakes. The accompanying soy sauce pitches sweet against sour, dark and viscous, pulling at the spoon like honey.
Or better yet: Start with a meal at Khao Kang, turn the corner and end with dessert here. Khao Nom is a lovely place to idle, under high ceilings with teardrop-shaped glass terrariums dangling from exposed pipes, at tables engineered from vintage sewing machines, with a cast-iron lacework of legs and foot pedals. There’s a pay telephone by the front door, perfectly restored, perfectly unusable.
Mr. Kosalanan flits back and forth between restaurants through a connected basement. His mother and his aunt hold the fort at Khao Kang, while his sisters-in-law take orders at Khao Nom. They are boundless in patience. There are so many sweets, all requiring names and translations, and they gently give you every one.