1. Prepare the Dough

• In a large mixing bowl (or stand mixer with the dough hook attached), combine the flour, pinch of salt, and sugar. Stir briefly to mix.
• Make a well in the center and pour in the warm milk. Sprinkle the yeast over the milk and let it sit for 5 minutes, or until the yeast becomes foamy.
• Add the softened butter and beaten eggs into the bowl. Begin mixing on low speed (or by hand with a wooden spoon).
• Knead for about 8 minutes until the dough becomes smooth and elastic. If kneading by hand, turn the dough onto a lightly floured surface and work it until it’s soft but not sticky.

2. First Rise

• Shape the dough into a smooth ball and place it in a lightly greased bowl.
• Cover with a damp cloth or plastic wrap and let it rise in a warm, draft-free spot for about 90 minutes, or until doubled in size.

3. Shape the Bomboloni

• Once the dough has risen, punch it down gently to release air.
• Roll it out on a lightly floured surface to about 1/2 inch thickness.
• Use a 2¼-inch round cookie cutter or the rim of a glass to cut out circles. Reroll any scraps gently to make more.
• Place the rounds on a parchment-lined baking sheet and cover lightly with a kitchen towel. Let them rest for another 10 minutes (5 if your kitchen is very warm).

4. Fry the Bomboloni

• Heat about 1 inch of vegetable oil in a heavy-bottomed pan over medium-low heat until it reaches 350°F (175°C).
• Fry the dough rounds in small batches, 5–6 at a time. Cook for about 1–2 minutes per side or until golden brown.
• Flip gently with a slotted spoon and drain the cooked bomboloni on paper towels.

5. Make the Custard Filling

• In a saucepan, whisk together the egg yolks, sugar, and cornstarch until smooth.
• Slowly add the milk while whisking to avoid lumps.
• Heat the mixture over medium heat, stirring constantly until it thickens and begins to bubble.
• Remove from heat and stir in the vanilla extract. Let it cool completely before using.

6. Fill the Bomboloni

• Once the fried dough has cooled slightly, use a small paring knife to make a slit in the center or side of each pastry, creating a pocket.
• Spoon the cooled custard into a piping bag or Ziploc bag with the tip snipped off.
• Gently squeeze about a teaspoon of filling into each bombolone until slightly plump.

7. Finish and Serve

• Dust generously with powdered sugar before serving.
• These are best enjoyed fresh but can be stored in an airtight container at room temperature for a day.