In a mixing bowl, place flour, eggs, yolk, zest of 1 lemon, orange zest, salt, and limoncello and mix well to form a firm dough, 8 to 10 minutes. Place in the refrigerator and allow to rest 30 minutes.
Remove from the refrigerator and cut golf ball-sized pieces of dough from the main batch. Roll each ball into a 1/2-inch thick dowel (rope) and cut each dowel into 1/2-inch pieces. Roll each piece into a ball and continue until finished with all dough.
In a 12 to 14-inch skillet with at least 3-inch sides, heat the oil to 375 degrees F. Drop enough balls in to cover about half of the surface of frying oil and cook until dark golden brown. Use a slotted spoon to turn them regularly, and expect them to puff up while cooking. As they finish, remove them to a tray covered with paper towels, and drain well. This should take at least 5 batches.
When all of the struffoli are cooked, heat the honey, lemon juice, and zest together in a wide 6 to 8 quart saucepan until quite warm, about 150 degrees F, and substantially thinner. Add struffoli to honey and stir carefully until well coated. Remove from heat and allow to cool 5 minutes in the pan, stirring regularly. Pour out into a large serving tray in the form of either a pyramid or a ring mold. Sprinkle with powdered sugar and serve.
Recipe copyright 2000, Mario Batali. All Rights Reserved.