The research is the easiest. The outline is the most fun. The first draft is the hardest, because every word of the outline has to be fleshed out. The rewrite is very satisfying.
I was asked by a group to write a song on the theme of brotherhood. This was before women's liberation, when brotherhood meant men and women both, so I wrote the song. Since I had always been very fond of the Passion Chorale, I wrote words to that great piece.