Lightly rub softened butter through cake mix and spread in base of pre lined tin. Bake for 20mins at 180C. Meanwhile beat the sour cream then mix with the eggs.
Drain cherries and spread on top of slightly cooled cake base. Top with sour cream mix and bake for 30 mins at 180 C . Place drained juice from cherries in pan add sugar and reduce to syrup consistency, use to pour over when serving.