Heat 1 tbsp olive oil in a skillet over medium heat. Add 1 crushed garlic clove and cook for 30 seconds until pale gold.

Add the fresh spinach and cook, stirring, for 3 to 4 minutes until fully wilted. Season lightly with salt. Transfer to a plate and spread out to cool. If using frozen spinach, skip the wilting step and simply season.

Once cooled, press the spinach firmly between your palms to remove as much water as possible. Set aside.

Hard-boil the eggs: lower them into boiling water and cook for exactly 9 minutes. Transfer to cold water, peel, and cool completely.

Soak the stale bread in the milk for 5 minutes, then squeeze it very dry with your hands. Discard the milk.

In a large mixing bowl, combine ground beef, ground pork, squeezed bread, whole egg, grated Parmigiano, parsley, minced garlic, salt, pepper, and nutmeg.

Mix with your hands for about 2 minutes until the mixture is uniform and slightly sticky. Do not overmix or the texture becomes dense.

Heat the oven to 180 C / 355 F.

Lay a large sheet of parchment paper on a flat surface. Place the meat mixture in the center and press it out with your hands into a rectangle roughly 30 x 22 cm and about 2 cm thick. Keep the surface as even as possible.

Lay the mortadella slices evenly over the meat, leaving a 3 cm border on all sides.

Scatter the squeezed spinach over the mortadella in an even layer. Sprinkle with the extra 20 g Parmigiano.

Line the three hard-boiled eggs end-to-end along the center of the rectangle, parallel to the long edge.

Using the parchment paper to help, lift the long edge closest to you and roll the meat firmly over the filling toward the far edge, forming a tight log. Seal the seam by pinching the meat together firmly. Seal both ends the same way.

Heat 2 tbsp olive oil in an oven-safe skillet or roasting pan over high heat. Lower the polpettone carefully into the pan, seam side down.

Sear for 3 minutes without moving until browned, then carefully turn and sear the other side for 2 to 3 minutes.

Pour the white wine into the pan and let it bubble for 30 seconds. Add the water or broth around (not over) the loaf.

Transfer to the oven and bake uncovered at 180 C / 355 F for 50 to 55 minutes, basting with the pan juices once halfway through, until the internal temperature reads 72 C / 160 F.

Remove from the oven and rest in the pan for 15 minutes before slicing.

Using a sharp serrated knife, cut the polpettone into slices about 2.5 cm thick. Each slice should reveal a clean cross-section of egg, spinach, and mortadella.

Spoon any pan juices over the slices before serving.