Pineapple Bun Bo Lo Bao

In a large bowl, combine flour, sugar, yeast, and salt. Gradually add warm milk and mix until a shaggy dough forms. Knead on a lightly floured surface for 5-7 minutes until smooth. Add softened butter and knead for another 5-10 minutes until the dough is elastic and passes the windowpane test. Place dough in a greased bowl, cover, and let it rise in a warm place for 60-90 minutes, or until doubled in size.

While the dough is rising, prepare the topping. In a separate bowl, cream together softened butter and granulated sugar until light and fluffy. Beat in the egg yolk until well combined. Sift in the all-purpose flour, baking powder, and optional milk powder. Mix until a soft dough forms. Do not overmix. Wrap the topping dough in plastic wrap and chill in the refrigerator for at least 30 minutes.

Once the bun dough has doubled, punch it down gently to release air. Divide the dough into 8 equal portions. Roll each portion into a smooth ball. Place the dough balls on a baking sheet lined with parchment paper, leaving space between them. Cover loosely with plastic wrap.

Take the chilled topping dough and divide it into 8 equal portions. Flatten each portion into a thin disc, about 4-5 inches in diameter. Carefully place one topping disc over each bun dough ball. Gently press down and smooth the edges to adhere the topping. You can use a knife to score a criss-cross pattern on the topping to mimic a pineapple skin.

Cover the topped buns loosely with plastic wrap and let them rise again in a warm place for another 30-45 minutes, or until visibly puffy. Preheat your oven to 180°C (350°F). Just before baking, gently brush the topping with a thin layer of beaten egg for a golden sheen.

Bake the pineapple buns in the preheated oven for 15-20 minutes, or until the topping is golden brown and crispy, and the buns are cooked through. Keep an eye on them to prevent over-browning. Remove from the oven and transfer to a wire rack to cool slightly before serving.