To make the brioche buns, heat the milk in a saucepan over low heat, until lukewarm. Combine yeast and half the milk in a bowl, stirring to dissolve. Stand in a warm place until foamy (8-10 minutes). Whisk remaining milk with egg yolks in a bowl and set aside.
Mix flour, sugar and a pinch of salt in the bowl of an electric mixer, fitted with a dough hook, until combined. Add yeast mixture and yolk mixture. Beat on medium speed until a smooth dough forms (4-5 minutes).
While mixing, gradually add one-third of butter at a time, beat until dough is elastic and pulls away from sides of bowl (8-10 minutes).
Transfer to a lightly buttered bowl, cover and stand until doubled in size (1½-2 hours). Knock back dough, knead on a lightly floured surface until smooth, shape into balls and place in an empty clean greased can.
Cover, stand until doubled in size (30 minutes-1 hour) Meanwhile, pre-heat oven to 190°C.
Brush top with egg wash, bake until golden and risen (25-30 minutes).
Remove from tin, place on a baking tray lined with baking paper, return to oven until sides are golden (5 minutes), cool on a wire rack.
Next, make the bunny chow filling.
Heat the oil in a pan then add the spices to temper. Add the sliced onions, and cook until golden brown. Then add the ginger and the chilli.
Pour in the de-gorged tomatoes, the tamarind, molasses and sugar. Over high heat reduce the sauce until thick then add the duck and herbs to heat through. Adjust the seasoning with salt then add the sesame seeds and pomegranate rubies.
Serve in a hollowed Brioche bun, sprinkled with fried onions, and some shredded mint.