Yeast Activation: Place yeast, sugar and water in a small bowl. Mix, then set aside for 10 minutes until it becomes foamy.

Place flour, cornflour and sugar in a stand mixer bowl fitted with a dough hook. Mix briefly to combine.

Add yeast mixture, oil and water. Mix on low speed for 3 minutes until a smooth ball of dough forms. It should be soft and elastic, not so sticky it gets stuck all over your hands. Adjust with a touch of flour/water if required to get the dough consistency right.

Cover with cling wrap and place in a warm dry place for 2 hours until it doubles in volume. (Note 3). Meanwhile, make Filling.

Remove cling wrap, scatter over baking powder. Return to stand mixer and mix on low for 2 minutes.

Turn dough out onto work surface, sprinkle with flour. Knead lightly to form a smooth round disc.

Cut dough into 4 pieces. Take one piece, roll into an even log, cut into 3 pieces (so 12 pieces in total).

Take one piece of dough, cover remaining with cling wrap or tea towel.

Roll into round 4.5" / 11 cm in diameter, making the edges thinner.

Place dough in hand, put 1 1/2 tbsp of Filling in the centre.

Pinch 8 pleats around the edges. Then gather the pleats together one by one to seal the bun. Pinch the top the twist.

Repeat with remaining dough - make 12 in total.

Cover buns loosely with cling wrap and leave in a warm place for 15 minutes.

Line a large bamboo steamer (or other steamer) with parchment paper punctured with holes (Note 4).

Place 6 to 8 buns on paper, cover with steamer lid.

Pour about 4 cm / 1 1/2 inches in a wok / pot (steamer should not touch water) and bring to rapid simmer over medium high.

Place steamer in wok, then cook for 12 minutes. Check water halfway through, top up if required.

Buns are ready when they spring back when touched, and the buns have formed a smooth skin.

Remove steamer from wok, serve warm!

Heat oil in a saucepan over medium heat. Add eschalots and cook for 2 minutes.

Add sugar, soy sauce, oyster sauce, sesame oil and water. Mix.

While stirring, slowly pour cornflour mixture in. Mix until smooth.

Stir in pork. Cook until sauce is thickened, 1 - 1 1/2 minutes (see video for consistency). Set aside to cool (thickens when cools).