In a large mixing bowl combine the flour, baking powder, baking soda, ground cinnamon, brown sugar and salt. Mix together.
In a separate bowl, whisk the eggs and yogurt until smooth.
Add in the vegetable oil and vanilla essence and whisk again.
Pour these into the bowl of dry ingredients and mix it all together until well combined to finish the cake mixture.
Pour the cake batter into the tin, on top of the caramel and apple layers.
Bake in centre of the oven for 45 minutes, or until a knife comes out clean.
Remove from the oven and allow it to cool for 10 minutes.
Then the fun part! Place a large plate over the cake tin and flip the cake over in one swift motion onto the serving plate. If you need to, tap or shake it a little to make sure the cake comes off in one motion.
Serve your gooey caramel apple upside down cake while warm with some vanilla ice cream.