These sensuous balls have their own day. It was on Friday, the third day of the third month of the lunar year. As is typical of food traditions in the capital, everyone who's anyone tries their hand at making or selling whatever the delicacy is. The currency on the streets of the old quarter on Friday was shiny, white and spherical. By day's end, I suspect that every Hanoian, at some stage, had had one or more of these balls rolling around on their tongue.
In a tradition that dates back to an ancient king, banh troi tau are made and bought to place on altars as offerings to ancestors and various deities. The locals fire up a few incense sticks, say a little prayer, proffer a little bow and the ceremony's complete. When the incense is a pile of powder on the floor, signifying that the ancestors have had their fill, frenzied consumption by mortals follows. I used to think that food laid on for the dearly departed went to waste. Not so!
However, as I skirted around the old quarter checking for ball action after an early lunch, it was evident that there were enough for every human, animal and insect ever to have graced the streets of Hanoi. Although banh troi tau are available throughout the year from a range of vendors, on Friday the ball purveyers had multiplied. Shops and sellers who normally flogged noodles or vegetables were selling the balls themselves or the ingredients to make them. It seemed that everyone was trying to get a cut of banh troi tau profit.
A lime white rice flour dough was being sold by the kilo, sugar syrup in plastic containers or BYO bowls and unrefined brown sugar cubes and sesame seeds by the handful. Getting the consistency of the dough right might prove problematic but the rest of the process is *ahem* a piece of cake. Flatten a small dollop of dough in the palm of the hand, place sugur cube on, wrap and roll to form a ball. Repeat until there is enough for the ancestors, gods and all living family members, drop into a pot of boiling water and retrieve with a slotted spoon when they come up for air. Put on plate, prettify with sesame seeds, prong with cake fork and deposit in eating hole.

Other ingredients to be found in these orbs include sesame paste, black sesame seeds, shredded coconut, ginger and green bean, all with sugar and all very sexy.
A serve of 15 balls on a plate will set you back a whopping 3000VND (USD18c, AUD26c). I had my balls in Thanh Ha street, around the back of the Dong Xuan market.