01 -
In a medium saucepan over medium heat, combine granulated sugar, cocoa powder, cornstarch, instant espresso powder, whole chocolate milk, vanilla extract, and butter. Stir continuously until smooth and thickened, then remove from heat and cool.
02 -
In a large bowl, mix cream-top milk, butter for dough, instant yeast, flour, granulated sugar, salt, and egg until a sticky dough forms. Transfer to a floured surface and knead for about 5 minutes until smooth and elastic.
03 -
Place kneaded dough in a lightly greased bowl, cover with a clean towel, and let rise in a warm place until doubled in size, approximately 60 to 90 minutes.
04 -
Turn dough onto a floured surface, roll out to 1.25 cm thickness, and cut out donut shapes using a donut cutter or two round cutters, reserving the holes for later consumption.
05 -
Heat the neutral oil to 180°C in a deep fryer or heavy-bottomed pan. Fry donuts in batches for 2 to 3 minutes per side until golden brown. Drain on paper towels to remove excess oil.
06 -
Coat cooled donuts generously with granulated sugar. Using a piping bag, fill each donut with the cooled chocolate custard, then garnish with chocolate shavings.