Heat the oven to 350ºF
Dice the apple into small cubes.
Cover the diced apple in orange juice to avoid oxidation (browning)
Cover the raisins in water inside a small bowl.
Blend the dry mix: In a large bowl, mix the flour, nutmeg, baking powder, baking soda, and cinnamon.
Blend and whisk the moist mix: Combine the sugar, eggs, and olive oil in a large bowl using a blender or mixer for 5 to 7 minutes. I did it by hand, but I recommend using a mixer.
Combine both mixes: Make a small hole in the middle of the dry mix and pour the moist mix inside. Stir to blend it all in a thick mix. Don´t worry, it is supposed to be very thick.
Drain the raisins and apples well and add them to the mix.
Prepare a cake mold or pan with non-stick oven paper: I recommend a 10-inch cake pan.
Bake for 45-50 minutes. Check if it is baked with a toothpick. If it comes out clean, it is ready.
Leave to cool off and dust with powdered sugar.