Shazam! The New Beginning
Written by Roy and Dann Thomas.
This was actually a 4 part mini-series starring the big red cheese. It was an attempt to sort of relaunch the story of Captain Marvel and bring the age old story of the Captain, Shazam, Black Adam and the supporting cast into the modern era.
One of the biggest changes the writers made to the origin story is that the personality of Billy Batson remains intact when he transforms into Captain Marvel instead of each of them being a totally separate identity.