good jazz piano

Andrew Hill
Randy Weston

2nd Gene Harris
Charles Brown

I absolutely love great piano players in the trio format. My favorites:
Marilyn Crispell
Russ Lossing
John Taylor 
Paul Bley 
Myra Melford
Masabumi Kikuchi (if you can get past the groaning!)
Bill Evans
Keith Jarrett
Vijay Iyer
E.S.T. (Esbjorn Svensson trio)
Brad Meldau
Marcin Wasilewski
Stefano Bollani 
Stefano Battaglia
Julia Hulsman

...there are hundreds more.  But really, if you want a treat check out Crispell's piano trio stuff on ECM

tord gustavsen

Lots of fabulous suggestions. I will add two that I did not see here....

Billy Taylor - he’s my favorite. The only word I can use to describe his playing is, well, “happy”... “A Touch of Taylor” would be a good place to start.

Mary Lou Williams ... one of the most influential jazz pianists that gets overlooked in conversations like this. Her conception is fabulous. Check out “Live at the Cookery”