This recipe is from the director of the Viet Way Center, Hanoi chef Nguyen Phuong Hai, who recently released his own cookbook in Vietnam. The banana and sweet potato provide the necessary starch, which rice flour lacks, so the dough is strong enough to deep-fry. — Tracey Lister and Andreas Pohl, authors of Made in Vietnam
- 1/2 Cup dried mung beans
- 2/3 Cups sugar
- A few drops of vanilla extract
- 1 sweet potato
- 1 banana
- 6 1/2 Ounces glutinous rice flour
- 1/4 Cup sesame seeds
- Vegetable oil, for deep-frying
To make the doughnut filling, rinse the mung beans under cold running water and place in a bowl. Cover with cold water and allow to soak for 2 hours.
Drain the mung beans well. Place in a steamer set over a saucepan of boiling water and cook for 20 minutes, or until soft.
Transfer the mung beans to a dry wok or frying pan. Add half the sugar and dry-fry over low heat until the sugar has dissolved. Remove from the heat and stir in the vanilla. Divide the mixture into 40 portions and shape into small balls.
Peel the sweet potato and steam it whole for 15 minutes, or until soft.
Weigh out 4 1/2 ounces of both the sweet potato and banana. Place in a mortar and pound until smooth.
Sift the flour into a bowl. Add the remaining sugar and 2 1/2 tablespoons warm water and mix to combine. Now add the mashed sweet potato and banana and lightly knead for 3–4 minutes, until you have a smooth dough. Cover with a damp cloth and leave to rest for 20 minutes.
Divide the dough into 40 equal portions, roughly the size of golf balls. Take one piece of dough at a time and flatten it into a disc. Place a mung bean ball in the middle, then encase it in the dough. Roll in the palm of your hands to form a ball, then dip the doughnut in the sesame seeds.
Repeat with the remaining ingredients.
Heat about 10 centimeters (4 inches) of oil in a wok. To test the oil, place the tip of a wooden chopstick into the oil — when bubbles slowly rise to the surface, the oil is hot enough to use. Fry the doughnuts in batches for 4–5 minutes per batch, until golden brown.
Drain well on paper towel and eat while still warm.
Recipe adapted from Made in Vietnam: Homestyle Recipes From Hanoi to Ho Chi Minh by Tracey Lister and Andreas Pohl (Hardie Grant, 2017)