1. In a small pot, whisk together 20 g plain flour and 100 ml water. Cook over medium-low heat, stirring constantly, until a thick paste forms (about 1 minute). Cool in the fridge for 5 minutes.

2. In a large bowl, combine 330 g plain flour, 30 g granulated sugar, 1 tsp salt, 8 g instant yeast, 1 egg, 120 ml warm milk, and the cooled tangzhong. Mix until a dough forms.

3. Add 30 g unsalted butter and knead for 8 minutes, until smooth and slightly tacky.

4. Place dough in a greased bowl, cover, and let rise in a warm place until doubled in size, about 1 to 2 hours.

5. On a floured surface, roll dough to 1.5 cm thickness. Cut out rounds using an 8.5 cm cutter. Place on a parchment-lined tray.

6. Gently cover and let rest for 30 to 40 minutes, until slightly puffed.

7. Heat oil in a deep pot to 180°C (350°F). Fry doughnuts 1 to 1.5 minutes per side, until golden brown. Drain on paper towels.

8. While warm, roll doughnuts in caster or granulated sugar to coat.

9. For the filling, beat 100 g cream cheese until smooth. In a separate bowl, whisk 300 ml double cream, 150 g icing sugar, and 2 tbsp matcha powder until slightly thickened. Add cream cheese and whisk until thick.

10. Once doughnuts are fully cooled, use a knife to make a hole in each. Fill a piping bag with matcha cream and pipe into each doughnut generously.

11. Serve and enjoy.