What is the book of mormans?

I just finished watching southpark the other day, the episode feature Jospeh Smith, who found the morman church, and claims that an angel told him to go dig up the gold plates and translate it into english, in order to restore the true concept of chrisitianity. And a new church was founded, which I think it is the protestant church.

mormon.org

I think it was actually the mormon church that was founded… the protestants were a couple of years earlier.