I feel like this weapon should offer some sort of passive effect over one big heal.

When eaten: Gain up to 50 Health (15 Second Recharge)
for 15 seconds, 80% of all damage dealt is returned as health
alt fire: Share Cake with a friend (Medium health pack and 40% of all damage dealt by them returns as health)
-50 Max Health On Wearer

its something a Heavy can eat BEFORE a fight to keep himself going.