Preheat the oil in your deep fryer to 325 degrees.
Combine the beaten egg with the milk in shallow bowl. Pour the breadcrumbs into another shallow bowl.
Bread the ravioli by dipping each one in the milk and egg, then into the breadcrumbs. Arrange the breaded ravioli on a plate and let them sit for 5 minutes so that the breading sticks.
When the ravioli has rested, drop a handful into the oil. Depending on the size of your fryer, you may want to fry the ravioli in batches so they aren't too crowded. Fry the breaded ravioli for 1-2 minutes or until they're golden brown. Remove them to a draining rack or a paper-towel lined plate.
When all the raviolis are cooked, arrange them on a serving plate and sprinkle Parmesan cheese over the top. Serve the dish with a small bowl of warmed marinara sauce on the side for dipping.