Whisk the flour, Cajun seasoning, Italian seasoning, cayenne pepper, 1/2 teaspoon salt and 1/2 cup water in a large bowl until smooth.
In a small food processor, grind fried onions and panko until fine. Place into bowl.
Add half of the cheese to the batter and toss to coat. Remove from the batter using a slotted spoon, letting the excess drip off, and add to the breading bowl. Coat and add to the oil one at a time. Fry until golden brown, 1 to 2 minutes; remove with a slotted spoon and drain on paper towels. Return the oil to 300 degrees F and repeat with the remaining cheese, breading and batter.
Serve with any dipping sauce of choice, or none at all!