01 -
In a large mixing bowl, combine flour, salt, and sugar. Create a well in the center and add warmed milk. Sprinkle yeast over the milk and let rest for 5 minutes, until foamy. Add softened butter and beaten eggs. Knead on low speed or by hand for 8 minutes, until smooth and elastic.
02 -
Shape dough into a ball and place in a greased bowl. Cover with a damp cloth and allow to rise in a warm, draft-free area for 90 minutes, or until doubled in size.
03 -
Roll dough onto a lightly floured surface to 1/2 inch thickness. Use a 2¼-inch cookie cutter to cut rounds. Place on parchment-lined baking sheet, cover, and let rest for 10 minutes.
04 -
Heat 1 inch of vegetable oil in a deep pan to 350°F (175°C). Fry bomboloni in small batches until golden brown on both sides. Remove with a slotted spoon and drain on paper towels. Cool slightly.
05 -
Heat milk in a saucepan. In a separate bowl, whisk egg yolks, sugar, cornstarch, and vanilla. Gradually add hot milk, whisking constantly. Return mixture to the saucepan and cook over medium heat, stirring, until thickened. Let cool.
06 -
Using a knife, create a small slit in each bombolone. Pipe custard filling into the center. Dust generously with powdered sugar and serve warm or at room temperature.