Colby Jack is a semi-hard cheese with a marbled look that is created by combining curds from Colby and Monterey Jack cheeses. I think the most challenging part of this cheese is running two cheeses in parallel and hoping that they both finish at the same time. If you decide to make this cheese, I recommend trying Colby and Monterey Jack individually and taking notes to help get the timing down.
Here are my notes from this cheese, along with a few pictures I took during the make: