Thanks to Zedupoca for the You Tube
I’m Gonna Sit Right Down And Write Myself A Letter was composed by Fred E. Ahlert with Lyrics by Joe Young. It was originally written for the Broadway musical Ain’t Misbehavin’ Fats Waller recorded in June 1935 with Herman Autrey, trumpet; Rudy Powell, reeds; Al Casey, guitar; Charles Turner, bass, Harry Dial, drums; and Fats on piano and vocal.
Fats’s piano solo on this tune is a subtle masterpiece; one of his best and without any showboating. His vocal was so good that a who’s who of vocalists in various categories of music—pop, rock, R&B,—covered it For more on that see here.
The song was recorded at a very high point in Fats’s career. It’s a great record.