In a large mixing bowl, combine 4 cups of all-purpose flour, ½ cup of sugar, 2 teaspoons of yeast, and 1 teaspoon of salt. Warm 1 cup of milk and ½ cup of melted butter until lukewarm, then pour over the dry ingredients. Add 2 beaten eggs, mixing until a smooth dough forms, about 5 minutes.

Lightly flour a clean surface and turn your dough out onto it. Knead the dough for about 8-10 minutes, until it becomes elastic and smooth.

Transfer the kneaded dough into a greased bowl, cover with a clean kitchen towel or plastic wrap, and place it in a warm area to rise for 1-2 hours, or until the dough has doubled in size.

Once the dough has risen, punch it down gently. Turn it out onto a floured surface and divide it into equal portions, rolling each into a ball.

In a deep pan, heat vegetable oil to 350°F (175°C). Carefully add a few doughnuts at a time, frying until they’re golden brown, about 1-2 minutes per side.

Once the Bomboloni have cooled slightly, take a piping bag filled with your creamy custard filling. Insert the tip into the side of each doughnut and fill them with the custard.

Finish by rolling the Bomboloni in powdered sugar for a sweet touch and enjoy immediately.