2 cups starter
3 cups bread Flour
1 teaspoon instant yeast
6 large eggs
1 large egg yolk
8 tablespoons unsalted butter, softened
2 teaspoons salt
2 teaspoons black pepper
3 cups freshly shredded Parmesan, Romano, or Asiago cheese, or a combination (*1)
3 raw eggs, colored if desired (optional)
AP flour
reserved egg white + 1 teaspoon cold water
Oiled pandoro, panettone pan, large soufflé dish, angel food cake pan, or another fairly narrow, round, deep pan (I use an angel food cake pan)
Casatiello Napoletano is usually stuffed with all the things you want to eat with it. This recipe, Cresia di pasqua, only includes cheese in the bread, and everything else is served on the side.
Combine dough ingredients except the cheese in the bowl of an electric mixer and paddle attachment, adding the flour a little at a time. Beat on medium speed for about 10 minutes, until the dough becomes shiny and satiny. It'll be very sticky; stop the mixer to scrape the sides and bottom of the bowl a couple of times during the mixing process.
Add the cheese, and mix until well combined. You may need to do it by hand.
Scrape the dough into a greased bowl or container, cover, and set it aside to rest/rise for 1 hour in a warm spot. Use the oil to help you stretch and fold the dough over two or three times, then allow it to rest/rise for 1 hour more.
Flour your work surface with about 1/2 cup of AP flour. Pull the dough out. Work enough flour in that you can shape the dough. Cut off a portion of about 5-6 ounces and set it aside in a lightly floured bowl; cover. Shape the remaining dough into a ball or log (depending on pan type).
Place your ball in the prepared pan.
Spritz with water, and allow it to rise until doubled, around 1 1/2-2 hours.
Towards the end of the rising time, if you are using them, place your 3 eggs on top of the dough, spaced out. Take the dough you set aside earlier, add flour if needed, and roll it out flat. You need to be able to get strips long enough to go over the eggs and sit on top of the loaf. Cut it into 6 nice strips and discard any extra. Place two strips over each egg in an x.
Put your oven rack in a lower position, just below the middle, and preheat the oven to 425°F.
Whisk the reserved egg white with the water and brush the top of the loaf.
Place the bread in the oven, bake 10 minutes, then reduce temperature to 350°F.
Bake anywhere from 20 to 30 minutes more (this will depend in large part on your pan), until it's brown and a thermometer in the center registers 200 F.
Remove the bread from the oven, and let it cool in the pan for 5 minutes before moving to a cooling rack. Remove the eggs (gently) with a spoon to let cool.
Cut into wedges and serve with a selection of meats, cheeses, and spreads. If you used them, peel and serve the baked eggs in wedges with a sprinkle of salt and pepper. 
Eat bread within two days.
*1 You can also work with other cheeses you have.
*2 While it is far from traditional, you can use mostly cheddar and add a small amount of chopped jalapeños when you mix in the cheese. Serve with Cincinnati chili.