In a medium bowl, combine the Cheddar, Monterey Jack, mayonnaise, Parmesan, butter, salt, pepper and seasoned salt.
Cut the loaf in half lengthwise, then into thirds or fourths. Evenly spread the cheese mixture onto the bread pieces. Wrap each piece in a foil "purse," leaving a little room at the top between the cheese and the foil.
The bread can either be frozen for later, or baked right away. If baking right away, place on a baking sheet and bake at 350 degrees F for 10 minutes. If cooking from frozen, bake on a baking sheet at 350 degrees F for 20 minutes.