This Apple Cinnamon Crumble Cake is a perfect, simple but mouth-watering treat where apples take centre stage! Topped with a delicious crumb topping, it's a lovely Fall dessert!
Pre heat the oven to 350F. Line a 9x9 inch pan with parchment paper and spray the parchment paper OR grease well with butter.
In a small bowl mix together the topping ingredients with a fork until crumbly and melted butter is all combined. Set aside.
In a small bowl, whisk the flour, baking soda, baking powder, ground cinnamon, ground nutmeg, salt and set aside.
In a large bowl, whisk melted butter with sugar until combined and a smooth paste forms.
Into the butter-sugar mixture, whisk in the egg, vanilla and yogurt until combined and smooth.
Add the flour mixture into the butter mixture and stir with a spoon until just combined. (The cake batter will be quite thick).
Stir the apple into the batter until just combined. Then, add the batter to the pan and pat down to make sure it's spread out to all the corners. Top with the crumb topping.
Bake for 40-45 minutes or until a toothpick comes out clean. Leave in the pan to cool.