• Preheat oven 350ºF/180ºC. Grease a 9in/22.5cm springform pan with butter or oil.

Dough

• Place flour, butter, and salt in the bowl of a stand mixer. Using the paddle and on the lowest speed, combine until a loose, sandy mixture is formed.
  3½ cups (450 grams) all purpose (plain) flour, 8 ounces (226 grams) unsalted butter, 1 teaspoon salt
• With the mixer still on low speed, add eggs one at a time until the mixture starts to come together. You may need a tablespoon or so of milk to bring the dough together.
  3 eggs, 2 tablespoons milk
• Turn the dough onto a board ( no need to flour at this stage) and knead a little to form a ball. Divide the dough in two portions - ⅔ and ⅓ - and shape into discs. Wrap each in plastic wrap and refrigerate while you prepare the filling.

Filling

• Place the ricotta in a large bowl and beat with a wooden spoon until broken up and becoming smooth.
  1 pound (450 grams) ricotta cheese
• Beat eggs in a small bowl. Reserve approximately 1 tablespoon. (You'll use this later to glaze the top of the pie.) Stir rest of the beaten eggs into ricotta.
  4 eggs
• Add remaining ingredients to the ricotta mixture and stir well to combine. Set aside.
  8 ounces (226 grams) mozzarella (cheese), 8 ounces (226 grams) ham, 4 ounces (115 grams) mortadella, 2 ounces (60 grams) prosciutto, 2 ounces (60 grams) salami, ½ cup grated pecorino Romano cheese, ½ teaspoon black pepper

Assemble and bake the pizza gaina

• On a lightly floured surface, roll out the larger portion of dough to at least a 16inch/40cm circle and line the greased springform pan. Trim the dough to the top of the pan.
• Spoon the filling into the pastry and smooth the surface.
• Roll out the smaller portion of dough to at least 9-inch/23cm. Use the springform pan as a guide to cut a 9inch/23cm circle. Fit the circle of dough over the ricotta filling.
• Brush pastry with reserved beaten egg then fold over extra pie dough to seal the filling. Brush with any leftover beaten egg. Cut a slit or two in the top of the pie. Bake until golden brown.
• Bake for 1 hour until golden brown.
• Cool in the pan for 2 hours if serving warm or refrigerate (in the pan) if it is to be eaten later cold. Remove from the pan for serving.