1. Preheat oven to 350F (175C). grease 9-inch (23cm) round baking pan lined with parchment paper and greased.
2. Caramelized apples: peel and grate the apples, then stir with the lemon juice and set aside.
3. Place butter, honey and milk in a pan and melt, stirring frequently over medium heat. Add grated apples and cook, stirring frequently, for about 4-5 minutes. Remove from heat and let cool.
4. Crumble: Combine the ingredients for the crumble topping together in a small bowl and Crumble together using your finger tips or a fork. Place in the fridge while making the cake.
5. Cake: in a large bowl or in bowl of stand mixer, whisk eggs, sugar and vanilla extract. Whisk until doubled in volume. Gradually and oil and milk while whisking. Add flour, baking powder, salt and stir until combined.
6. Pour the batter to the prepared pan, spread the caramelized apples on top, then sprinkle the crumble on top.
7. Bake for 35-40 minutes. Let cool for 10 minutes in the pan, release from the pan and let cool completely.