I had 2 bananas on their way out of "snackville" and on their way to TOO RIPE land so I went through my newly organized recipes and found this: Caramel Walnut Upside Down Banana Cake (whew!).
This was very easy to make. I did the topping first and as it cooled in the pan, I assembled the rest of the ingredients and by the time I was finished, the topping was cool. The caramel DID overflow while baking, so I suggest putting it on a cooking sheet lined with a silicone sheet or foil. It also seemed to brown quickly while the cake still was not finished, so be aware of that too. The cake part is very moist and the caramel is so rich. Mine did not harden like some of the reviews mentioned, but then again, I ate it pretty quickly upon getting out of the oven. :-) Also, I had no problems with it coming cleanly out of the pan when I over turned it onto the plate.