Step 1: Make the Bomboloni Dough

Start by combining the bread flour, 00 flour, granulated sugar, and yeast in the bowl of your stand mixer. Stir to combine all the dry ingredients. Then, add the softened butter, eggs, lukewarm milk, vanilla paste, and salt. Attach the dough hook to the mixer and knead the dough on a low speed (speed 2 on a KitchenAid mixer) for about 10 minutes. The dough should become smooth, elastic, and slightly tacky to the touch.

If the dough feels too sticky, avoid adding excess flour. Instead, you can use a small amount of flour to help shape the dough, but remember that the dough should remain a bit sticky. This tackiness is what will help create the fluffy texture of the doughnuts.

Once the dough is ready, shape it into a smooth ball and place it in a greased bowl. Cover the bowl with plastic wrap and allow the dough to rise for 2-3 hours, or until it has tripled in size. This proving time allows the yeast to work, creating the light, airy texture of the dough.

Step 2: Roll and Cut the Doughnuts

After the dough has risen, punch it down gently to release the air. Turn the dough out onto a clean, unfloured surface and knead it briefly to smooth it out. Then, roll the dough out into a rectangle about 1.5 cm (½ inch) thick. Using a round cookie cutter (about 3.5 inches in diameter), cut out doughnut shapes from the dough. You can also use a glass or any other round object that is similar in size.

Place the cut doughnuts on a surface lined with parchment paper. Make sure there is enough space between each doughnut, as they will expand during the second proving. Cover the doughnuts loosely with plastic wrap and let them prove for another 1-1.5 hours, or until they have tripled in size. The doughnuts should feel light and airy when pressed gently.

Step 3: Make the Pastry Cream

While the doughnuts are proving, prepare the pastry cream. Start by whisking the egg yolks, sugar, vanilla, and lemon zest in a large bowl. Add the cornstarch and whisk until smooth.

In a saucepan, heat the milk over medium heat until it is hot, but not boiling. Once the milk is hot, remove it from the heat and let it sit for a minute. Slowly pour the hot milk into the egg mixture while whisking constantly. This gradual pouring prevents the eggs from scrambling.

Return the mixture to the saucepan and heat it over low heat, stirring constantly, until the cream thickens. This can take about 10-15 minutes, so be patient. Once the cream has thickened to a custard-like consistency, remove it from the heat. Pour the pastry cream into a clean bowl and cover it with plastic wrap, ensuring that the wrap touches the surface of the cream to prevent a skin from forming. Allow it to cool to room temperature.

Step 4: Fry the Bomboloni

Once the doughnuts have proved and the pastry cream is ready, it’s time to fry the Bomboloni. Heat a deep pan or pot of oil to around 170°C (337°F). If you don’t have a thermometer, you can test the oil by dropping a small piece of dough into it. If it sizzles and rises to the surface, the oil is hot enough.

Cut the parchment paper into squares, with each square large enough to hold a doughnut. Carefully drop the doughnuts, with the parchment paper underneath, into the hot oil. Using tongs, remove the parchment paper immediately. Fry the doughnuts in batches, making sure not to overcrowd the pan. Fry each doughnut for 2 minutes on one side, then flip and fry for another 2 minutes on the other side until golden brown.

Remove the doughnuts from the oil and drain them on paper towels for about 2 minutes to remove excess oil. While the doughnuts are still warm, roll them in caster sugar or powdered sugar.

Step 5: Fill the Bomboloni

Once the doughnuts have cooled slightly but are still warm, it’s time to fill them with the delicious pastry cream. Use a small knife to make a small incision in the side of each doughnut. Then, use a piping bag fitted with a nozzle to fill each doughnut with pastry cream. Be generous with the filling, as the pastry cream should be a delicious surprise with each bite.

Step 6: Serve and Enjoy

Bomboloni are best served immediately after they are filled, while they’re still warm. The crispy, sugary exterior combined with the soft, creamy filling creates a treat that is nothing short of magical. Whether you’re enjoying them as an afternoon snack or serving them as part of a festive occasion, Bomboloni are sure to impress.

You can also experiment with other fillings, such as Nutella, fruit jams, or whipped cream, for a fun twist on the traditional Bombolone. For a truly indulgent experience, try serving Bomboloni with a cup of espresso or hot chocolate, making it a perfect treat to enjoy with loved ones.