Preheat oven to 200C and grease a 9inch cake pan with olive oil, or butter and flour it till its coated well. Once coated well add a parchment paper
Sift flour, almond flour, baking powder, baking soda in a bowl and mix
With a stand mixer or handheld mixer, beat the eggs and sugar for 3-4 mins until it becomes thick and creamy
Gradually add in the olive oil while mixing on medium to low, then add the juice, zest and the vanilla
Fold dry ingredients with wet and mix until combined (do not overmix)
Spread the salted caramel on the bottom of the cake pan, and top with the sliced oranges or tangerines (you can totally omit this step)
Pour the batter over the oranges, place in oven and lower temp to 180C
Bake for 45-55 mins or until a toothpick comes out clean
Once it cools down, carefully flip and peal the baking paper