• Preheat the oven to 180 degrees Celsius. Line a muffin pan with muffin liners.

Crumble

• Cut the cold butter into small cube sizes, i.e. 1 cubic centimeter.
• Method 1 (longer + more hands): Add all the crumble ingredients and the cold butter cubes into a large bowl. Get your hands in and start rubbing the butter into the dry ingredients. Keep rubbing until the mixture resembles breadcrumbs.
• Method 2 (quicker + cleaner): Using a food processor, mix up all the dry ingredients and the cold butter cubes until breadcrumbs texture is achieved.
• Leave in fridge as you prepare the muffin batter to keep the butter from softening.

Muffins

• Sift the flour, baking powder, baking soda, salt and cinnamon together into a bowl. Leave aside these dry ingredients.
• Peel and cut the apples into bite-sized cubes.
• Cream the softened butter, oil and sugar in a large mixing bowl with an electric mixer until pale and smooth, around 4 minutes. Add the egg and the vanilla extract into the mixture, continue mixing to incorporate.
• Add 1/3 of the dry ingredients and 1/2 of milk into the large mixing bowl. Fold until just combined. Repeat the process with another 1/3 of the dry ingredients and 1/2 of the milk. Do one last fold procedure with the remaining 1/3 dry ingredients. Just as the batter is just about to come together (you should still be able to see some flour), then add the apples in and fold just to combine.
• Using an ice cream scoop or 2 spoons, scoop the batter evenly in your prepared pan – filling 2/3 of the muffin liner. * Top the muffins with crumble. Bake for 20-22 minutes, or until a clean toothpick comes out when you insert it into the centre of the cupcake. Let the muffins cool for 10 minutes.
• Best served with warm custard sauce! :)