When ready, preheat the oven to 450°F.
Pour the remaining oil mixture into a 12-inch cast-iron skillet. Use a pastry brush to coat the skillet.
Add half the dough to the skillet and work the dough to the edges. Use your fingers to create dimples in the dough.
Top the dough with 1 cup of shredded mozzarella cheese.
Fold the other half of the dough out onto a sheet of parchment paper. Use your hands to form the dough into a 12-inch circle. Invert the parchment paper over the cheese and carefully peel back the paper, leaving the top layer of dough in the skillet.
In a small bowl mix together butter, garlic, parmesan, parsley, and salt. (This is the garlic butter.)
Use your fingers to gently dimple the top of the dough. Brush the garlic butter over the top of the dough.
Top with the remaining mozzarella cheese and the cheddar cheese.
Bake for 18-20 minutes, or until golden brown and the cheese is bubbling. (If you want the bread cut into pieces, remove it after 16 minutes, cut, and then put the bread back in the oven for the final two minutes.)
Serve hot with a marinara sauce for dipping.