In the bowl of the stand mixer, add the egg, milk, sugar, salt, flour, and yeast.
Mix on speed 1 for 5 minutes to obtain a homogeneous dough.
Knead on speed 2 for 10 to 15 minutes, until the dough pulls away from the sides.
Add the butter cut into cubes and knead on speed 1 until completely incorporated and the dough pulls away.
Let the dough rest for 1h to 1h30 at room temperature (20-25°C), until it doubles in volume.
Deflate the dough to release the air and form a ball.
Place the dough in the bowl covered with plastic wrap and let it rest for 12 hours in the refrigerator .
Take the dough out of the refrigerator and let it rise to room temperature for 5 to 7 hours.
Deflate the dough to release the air and cut into pieces of 70g.
Shape the pieces using a cookie cutter.
Let the mannele rest at room temperature for 1h30 to 2h.
Brush the mannele with egg and bake them.