I can say without hesitation that the biscuit and gravy that I had at Bab's Delta Diner yesterday was the best I've ever had.
The only fly in the ointment is that it's the only time I've ever had this dish.
The biscuit was large, hot, tender, and a bit crumbly; one was plenty. The gravy was served alongside the biscuit in a white ceramic dish; it was almost thick enough to support a utensil, was well-spiced, and featured small to large chunks of crumbled sausage.
I had ordered their mini egg breakfast (one egg, taters, two strips of bacon, and toast) and substituted the biscuit/gravy combo for the toast for an additional $1.49. A "biscuits and gravy" dish wasn't offered on the menu although one can order potatoes covered with the gravy plus a biscuit.
Bab's Delta Diner is located at 770 Kellogg Street on the Suisun waterfront. It opens at 5:00 for breakast and lunch and draws quite a crowd on weekends.