Custard Bao

Instructions

1. Prepare the dough
   In a large bowl, combine flour, sugar, yeast, and baking powder. Make a well in the center and add warm milk, water, and vegetable oil. Mix until a dough forms, then knead on a floured surface for 8-10 minutes until smooth and elastic. Place in an oiled bowl, cover with a damp cloth, and let rise in a warm place for 1 hour or until doubled in size.
2. Make the custard filling
   While the dough is rising, make the custard filling. In a medium bowl, cream together butter and sugar until light and fluffy. Add egg yolks one at a time, mixing well after each addition. Stir in custard powder, condensed milk, and vanilla extract until smooth and well combined. Cover and refrigerate for 30 minutes to firm up.
3. Form the buns
   Punch down the risen dough and divide into 12 equal pieces. Roll each piece into a ball, then flatten into a 4-inch circle, making the edges thinner than the center. Place 1 tablespoon of chilled custard filling in the center of each circle. Gather the edges and pinch firmly to seal completely. Place each bun, seam side down, on individual squares of parchment paper.
4. Let the buns rise
   Place the formed buns on a tray, leaving some space between each bun. Cover with a damp cloth and let rise for another 30 minutes until slightly puffy.
5. Steam the buns
   Arrange the buns in a steamer basket lined with parchment paper, leaving at least 1 inch between buns as they will expand. Steam over high heat for 12-15 minutes. Turn off the heat but do not open the lid; let the buns rest for 2 minutes before removing from the steamer.
6. Serve
   Transfer the steamed buns to a serving plate. Serve warm for the best taste and texture. The custard filling should be creamy and slightly molten when the buns are freshly steamed.