For the crumb

1. In a bowl, give the flour and cinnamon powder a good mix.
2. Rub in the butter using your fingertips.
3. Once it looks like coarse breadcrumbs, mix in the brown sugar.
4. Press a piece of plastic against the surface and refrigerate.

For the cake

1. Preheat oven to 170C.
2. Arrange cupcake liners in a muffin pan or you can also bake in a greased 8×8-inch cake pan.
3. Sift the 2 cups flour, baking powder, baking soda, and salt.
4. In a mixing bowl, cream the butter and sugar with a mixer until light, for about 2 minutes.
5. Add the eggs one by one, beating for about 1 minute after each addition. Add in vanilla extract.
6. Reduce the mixer speed to low and add the flour mix and the buttermilk alternately.
7. Remember to start with the flour mix and end with the flour mix too.
8. Fold in the apples gently.
9. Pour spoonfuls of the batter in the muffin cups or baking pan.
10. Take the crumb mix, break it up with a fork.
11. Scatter the crumbs on top of the cake. It is okay it the crumbs are irregular and has large bits.
12. Bake the little cakes for 20-25 minutes and a whole cake would take about 50-60 minutes.
13. The crumbs should be golden and a skewer inserted into the center of the cake comes out clean.
14. Transfer the cake to a rack and let it cool.