In a bowl, add the butter, brown sugar, sugar, cinnamon and flour. Use a fork incorporate all of the ingredients until a coarse crumb forms. Chill until ready to use.
3. Step
In a bowl, add the flour, cinnamon, nutmeg, salt, and baking soda, stir to combine.
4. Step
In a large bowl, add the butter, sugar, and maple syrup. Whisk until fully incorporated,
5. Step
Add the egg and vanilla to the bowl with the butter and mix until fully incorporated.
6. Step
Add half of the flour mixture, and mix until just combined. Add the second half of the flour mixture and mix until there are streaks of flour still showing, making sure to not overmix.
7. Step
Pour the lemon juice over the apples then gently fold the apples into the batter.
8. Step
Spread batter evenly into a greased 9-inch (23 cm) square cake pan.
9. Step
Sprinkle crumble mixture over the top, creating different size crumble pieces by squeezing some small clumps together in your hands for varying texture.
10. Step
Bake for 25 minutes, or until toothpick comes out clean, cover with foil the last 5 minutes to prevent the top from over baking.
