Long John Baldry - "Don't Try to Lay No Boogie-Woogie on the King of Rock and Roll

A classic. Reg Dwight (Elton John) awesome on piano. Elton John and Rod Stewart produced. The original "Maggie May" (of Rod Stewart song fame) sings on this album. I was just floored when I first heard this album in early '70's (which I guess means either I'm easy or it's great). For more info on the album and some of the interesting back story, here is a link to the Wikipedia article:

Long John Baldry - "It Ain't Easy" Album (1971; re-released 2005)