Peel the apples and cut them into smaller pieces
Put apple, sugar, and water in a saucepan and cook under lid on medium heat until the apples are tender
Take the apples off the heat and use a hand blender to mash them into apple sauce
In a large bowl, mix flour, baking powder, and baking soda
Whip the oil with the flour with a whisk - this might create small lumps
Lubricate the spring form pan with a bit of vegetable oil or vegetable butter
Zest the lemon using a grater with fine holes
Press lemon juice of 3-4 lemons (till there is 2 ½ dl)
Add apple, lemon zest, and lemon juice to the flour and stir it quickly together. The dough will already start to rise due to the lemon juice (which naturally contains acid)
Put the dough in the springform pan
Bake the cake in the oven at 175° C for 25-30 minutes
Let the cake cool
Remove the cake from the springform pan and place it on a platter