Mozzarella is sold in rounds about the size of a small fist. Because it has no rind it’s packed in plastic bags, surrounded by water to keep it fresh. You’re more likely to find buffalo ...
Bring to a simmer while stirring. Cook at a simmer for 3 minutes. Stir in half the mozzarella. Transfer to a 9-by-13-inch baking dish. Bake for 18 minutes. Top with remaining mozzarella and feta.