Upside-down cakes were developed centuries ago when much of the cooking was done in cast- iron skillets. Cake batter was poured on top of fruit and sugar and placed over an open fire to cook. To get the cake out, it was easiest to just flip the whole thing upside down! Pineapple upside-down cake was particularly popular during the ’50s and ’60s since it was such a pretty, colorful cake to show off to guests.