While on an archaeology trip to Rome after recieving a MacArthur Fellowship, Frank found what he thought were the medical writings of Greek physician Aegimus. What he really found was the first known mention of cheesecake since the invention of writing.
Intending to use the remainder of his funding studying this new document Frank was perplexed. It seemed that a piece of the document containing the finalization of the recipe was damage and/or missing. So after long contemplation he decided that the Greeks must have had some means of sweetening the cake, somehow, someway. That’s when it hit him. Natural fruit. Hence the raspberries.