For the sauce: In a saucepan over medium heat, warm the 1/2 cup olive oil.
Add the garlic and red pepper flakes and cook, stirring, until the garlic is soft but not browned, about 1 minute.
Add the tomatoes and their juices and simmer until the sauce is thickened, about 6 minutes. Season with salt and black pepper. Set aside.
Preheat an oven to 200°F.
For the fried mozzarella: Drain the cheese from its liquid. Place the cheese on a paper towel-lined baking sheet and pat dry.
If your cheese balls seem pretty big, halve or quarter them into bite-size pieces. Once they get the panko breading on them, they will be a lot bigger.
In a bowl, whisk together the eggs and milk.
Put the egg mixture and bread crumbs in separate wide, shallow bowls. Combine the panko with the teaspoon of salt and Parmesan in another wide, shallow bowl. (*If you only have one shallow bowl, use it for the panko. It will help you immensely with the breading process.)
Roll the cheese in the flour, dip into the egg mixture and coat with the bread crumbs, shaking off the excess after each step.
Repeat the breading process one more time for each cheese piece.
In a large, deep sauté pan over medium-high heat, pour the oil to a depth of 3 inches and heat to 350°F on a deep-frying thermometer.
Working in batches, fry the cheese until golden, about 45 seconds (or until golden brown-watch them carefully as oven temperatures may vary). If you notice that your thermometer’s reading decreases, wait for a little while until the oil gets back up to the proper temperature.
Transfer the fried cheese to a paper towel-lined plate and season with salt and black pepper. Place the cheese on a wire rack set over a baking sheet and keep warm in the oven while frying the remaining cheese.
Serve with the warm tomato sauce.