In a large bowl mix crumbled yeast, sugar, milk, and flour, until you obtain a smooth dough.

Cover with cling film and allow to rise for 1 hour at room temperature and then 12 hours in the refrigerator.

Once the resting time has elapsed, put the flour on your work surface and use your hands to make a crater in the center.

Add eggs, the crumbled yeast and the sugar. With a spatula, move the flour from the edges of the crater towards the center, onto the other ingredients, to let it absorb a little, then add the Biga. Still helping yourself with the spatula, start mixing the ingredients, always collecting the flour from the edges.

Add the butter, then knead until smooth.

Spread it with your hands and fold it on itself, then turn it clockwise and repeat the folding. Do the same thing two more times, then make a ball, put it into a bowl covered with cling film and let it rise for 1 hour at 26-28° then for 12 hours in the fridge, then for 2 hours at 26-28° C. To obtain 26-28°C, place a saucepan of hot water in the oven, put the dough inside and close the oven.

After the resting time of the 2nd dough, put the flour on your work surface and use your hands to make a crater in the center.

Add eggs and with a spatula move the flour from the edges of the crater towards the center, onto the other ingredients, to let it absorb a little, then add the 2nd dough.

Add sugar, salt, and lemon zest. Knead until the dough comes together.

Add the room temperature butter a little at a time. Before adding more butter, make sure the previous one is fully incorporated. Knead until the dough comes together.

Open the vanilla pod in the center with a knife lengthwise and scrape out all the vanilla seeds, adding them to the mixture.

Add the candied fruit and raisins and quickly incorporate.

Wet your hands. Spread it with your hands and fold it on itself, then turn it clockwise and repeat the folding. Do the same thing two more times, then make a ball, place it in a bowl covered with cling film and let it rise for 2 1/2 hours.

Once the time has passed, transfer the dough to the work surface. Spread it with your hands and fold it on itself, then turn it clockwise and repeat the folding. Do the same thing two more times, then make a ball, put it in the mold and let it rise for 5 hours, or until it rises to 2 cm below the edge of the mold. At this point let the dough rest for 3 minutes in the air to form a crust on top.

With a sharp knife, cut a cross on the surface of the panettone and add a knob of butter in the center.

Place in a preheated static oven at 175° for 50 minutes. After 5 minutes, place a baking tray on the top shelf of the oven to prevent the panettone from burning. (I used a gas oven for cooking, if you use an electric oven you have to reduce the temperature and cooking times by about 10%).

Remove your panettone from the oven when you see that it is golden brown on the surface. If you are unsure whether it is cooked to perfection, use a long toothpick, one of those used for a skewer, and delicately skewer the panettone; if it comes out dry, when you remove it, the panettone is cooked.

Thread the panettone with skewers and turn it over. Let it cool for 6 hours upside down.