How to make it

1. In a large bowl, combine flour, sugar, yeast, and salt.
2. Add warm milk, melted butter, and egg to the dry ingredients. Mix until a soft dough forms.
3. Knead the dough on a lightly floured surface for about 5 minutes until smooth.
4. Place the dough in a greased bowl, cover, and let rise in a warm place for 1 hour or until doubled in size.
5. Preheat the oven to 350°F (175°C).
6. Roll out the dough to about 1/2 inch thick and cut into circles to fit the doughnut pan.
7. Place the dough circles into the greased doughnut pan wells.
8. Bake for 12-15 minutes or until lightly golden and puffed. Cool on a wire rack.
9. For the pastry cream, blend pistachios into a fine powder.
10. In a saucepan, heat milk and half the sugar until just boiling.
11. In a bowl, whisk remaining sugar, cornstarch, and egg yolks. Slowly whisk in hot milk.
12. Return the mixture to the saucepan and cook over medium heat until thickened.
13. Stir in vanilla and pistachio powder. Chill until ready to use.
14. For the glaze, melt white chocolate chips and cream together until smooth.
15. Once doughnuts are cool, fill each with pistachio cream using a piping bag.
16. Dip the tops of the filled doughnuts in the white chocolate glaze.
17. Sprinkle with crushed pistachios before the glaze sets.