Cut block of mozzarella into small cubes, about a ½ inch (1 ¼ cm).
Cut pepperoni in half.
In a mixing bowl, combine hash browns, Italian seasoning, salt, garlic powder, and egg. Mix well.
Grab a small handful of the hash brown mixture and flatten out in the palm of your hand.
Place 1 or 2 slices of pepperoni and a cube of cheese on top.
Fold the hash brown mixture around the cheese and pepperoni. Squeeze and compress until the mixture completely covers the filling and stays in a cylindrical form. Repeat until all of the mixture is used.
Freeze tots for 20+ minutes.
In a large saucepan, heat oil to 350˚F (180˚C). Fry tots in batches, three at a time, until golden brown. Drain on paper towel.