How to cook
Put the spinach in the bowl along with the oil.
Blend with a blender until a smooth mixture is obtained. Be careful not to have whole leaves inside.
Crack the eggs in another bowl. Add sugar and vanilla.
Beat with a mixer until a white and fluffy cream is obtained. Stop the mixer and add the spinach mixture.
Turn on the mixer again and at low speed, beat, by adding small amounts of flour (mixed with baking powder).
Transfer the mixture into a cake tin with a removable bottom, which is lined with baking paper.
Bake the cake layer in a preheated oven at 340°F (170 degrees) until it's fully baked.
Take it out and leave it to cool completely before cutting the spinach cake layer.