Enemy Pie

Did you ever read about Enemy Pie?  The story was about a boy who had an enemy.  He keeps a list of his enemies in his tree house. His enemy was nice to him on their little play date.  The boy had only one enemy on his enemy list.  When it was dinner time they ate mac and cheese.  When it was dessert they ate the enemy pie.  Then they became friends. The book was very good. Did you find the secret?
Amelia