In a large bowl, whisk together all-purpose flour, granulated sugar, active dry or instant yeast, and a pinch of salt. Gradually pour in warm milk, followed by beaten eggs and melted unsalted butter. Mix until combined. Knead the dough on a floured surface for about 8–10 minutes, until it’s smooth and elastic, then shape it into a ball.

Place the kneaded dough in a lightly greased bowl and cover it. Let it rise in a warm area for 1 to 2 hours, or until the dough has doubled in size.

Punch down the dough to release air, then turn it onto a floured surface and divide it into equal portions, shaping each piece into a ball. Place on parchment paper, cover with a towel, and let them rise again for 30 to 60 minutes.

Heat vegetable oil in a deep fryer or heavy pot to 350°F (175°C). Fry a few dough balls at a time for about 2–3 minutes on each side until golden brown. Transfer to a paper towel-lined plate.

Once cooled slightly, fill each doughnut with pastry cream using a piping bag.

Roll each filled Bomboloni in powdered sugar before serving.