Prepare the dough by combining ricotta, flour, cornstarch, egg, sugar, baking powder, and salt
Make ricotta by combining whole milk, heavy cream, and lemon juice
Prepare sweet lemon zest by combining lemon zest and sugar
Create mascarpone filling by mixing mascarpone, powdered sugar, lemon syrup, and vanilla paste
Form dough into chestnut-shaped pieces and fry until golden
Fill castagnole with mascarpone filling
Coat with sweet lemon zest
