Pour flour, water, and brewers’ yeast in a bowl and mix.
Make a homogeneous pat, then cover the bowl with plastic wrap. Let rest for 1 hour in a turned-off oven.
Pour in a bowl flours, with an egg in the middle, butter, sugar and lemon zest.
Mix with your hands, and pour milk little by little.
Add the first dough.
Mix with your hands for 20 minutes to get a homogenous and solid dough. If you use the pasta maker machine, work it until it will be strung to the hook.
Cover the bowl with a plastic wrap, and let it rise in a turned-off oven for 2 hours.
Roll the dough to obtain a puff pastry of 2 cm / 0’78” inch of height.
Use a circular pasta cutter with 8 cm / 3’14 inch of diameter to make some disks. With a plastic bottle cap press in the center of the pasta disk to get the donuts. Put them on a baking tray covered with bakery paper, with some scattered flour.
Cover with plastic wrap for one hour.
When the dough is ready, pour some seeds oil in a frying pan. When the oil will be hot enough, fry one at the time the bomboloni, turning them upside down a couple of times.
When the bomboloni will be gilded, drip the oil with a slotted spoon. Put them upon bakery paper scattered with sugar for the icing, until the entire surface is covered.