Preheat the oven to 350° F. Grease the bottom and sides of a 6-quart Dutch oven or large oven-proof pot with butter.
In a large bowl, combine the turkey, mozzarella, and gravy. Stir everything to combine.
In another large bowl, combine the green and orange vegetables and stir to combine.
On a well-floured surface, roll out the pasta dough into a round large enough to drape over your pot with enough overhang to cover the sides and top completely. The sheet should be about an 1/8th thick, about thin enough so see through.
Place the pasta sheet inside the buttered pot and position so the sides are covered and the excess is draped over the sides.
To fill the timpano: add 3 cups of stuffing to the bottom of the pot and spread in an even layer. Next, add half of the turkey mixture, spreading in an even layer. Add the vegetable layer, spreading out evenly. Add the cranberry sauce and spread in an even layer. Next, arrange the egg halves yolk side down, spaced out evenly. Add the mashed potatoes and spread in an even layer. Add the remainder of the turkey mixture, spreading evenly. Lastly, add the remaining 3 cups of stuffing and spread in an even layer. Fold over the excess pasta over the top of the filling, being sure it’s completely covered.
Place the lid on the pot and bake for one hour. Remove the lid and continue baking another 20-30 minutes, until the top is golden-brown and the internal temperature reaches 120 degrees.
Allow the timpano to cool for at least one hour in the dutch oven then place a cutting board or large serving platter on top and gently and swiftly flip it over then remove the pot. Allow to cool another 30 minutes to 1 hour before slicing.
To serve, slice the timpano into wedges and drizzle with a little of the remaining gravy.