Evidently the German troops thought the British plum jam was a delicacy.
The British despised it; it was a food joke in their army. On the other hand, the Germans got tired of their sausages and hard bread.
In North Africa, believe it or not, the German rations often consisted of sardines. Or spaghetti. As a side-note, the Russians use caviar as army rations. Or they used to. I don’t know if they still do.