Hong Kong Style Cocktail Buns (Sponge & Dough Method)

Crush ice and measure 90ml ice water for later use.

Add 90ml ice water, 3g sugar, 2.5g instant yeast, and 150g high gluten flour into the mixing bowl.

Knead at low speed until cohesive dough forms; thin membrane stage is not required.

Cover dough and ferment at room temperature for 2.5 hours until expanded to about 2.5 times its size.

Mix 70g softened butter and 60g powdered sugar with a spatula until smooth and creamy.

Add 10g cake flour, 15g milk powder, and 25g desiccated coconut; mix until a smooth filling dough forms.

Wrap the filling in plastic wrap and chill in a 4°C refrigerator until firm.

Mix 24g softened butter, 20g sugar, and a pinch of salt (about 0.5g) until pale and smooth.

Gradually add 20g egg while whisking, then stir in 34g all-purpose flour until smooth.

Spoon Mexico batter into a piping bag, push out air bubbles, and seal for later use.

To the fermented sponge dough, add 15ml ice water, 40g all-purpose flour, 20g high gluten flour, 1g instant yeast, 40g sugar, 8g milk powder, 20g egg, and 3.5g salt.

Knead at low speed until a cohesive dough forms, then add 20g softened butter and knead at medium-high speed until smooth with a windowpane test.

Shape dough into a ball, place in a covered bowl, and chill in a 4°C refrigerator for 30 minutes to rest.

Take out chilled filling, divide into 8 equal portions (about 23g each), and roll each into a cylinder.

Remove rested dough, press gently to degas, and divide into 8 equal portions (about 50g each).

Round each dough piece into a smooth ball, cover with plastic wrap, and let rest at room temperature for 10 minutes.

Flatten dough into an oval, smooth side down, and place a filling cylinder in the center. Fold edges over, pinch seam tightly, and roll gently into an oval log.

Place shaped dough rolls on parchment-lined baking sheet. Put into oven with a container of hot water at the bottom, proof for 40 minutes until nearly doubled in size.

Remove proofed dough and hot water from oven, then preheat oven to 190°C (without fan convection).

Gently brush a layer of egg wash on top of the proofed dough rolls.

Pipe two horizontal lines of Mexico batter across each dough, then sprinkle white sesame seeds between the lines.

Bake in the preheated 190°C oven on the lower-middle rack for 12–15 minutes until golden brown, then transfer to a wire rack to cool.