Coffee Crumb Cupcake Recipe

To make the crumble topping: In a food processor, blend the walnuts, brown sugar, and cinnamon until combined. Set aside 1/4 cup of this mixture for the cake filling.

Add the flour, butter, and vanilla into the processor and blend to form the crumble. Set aside in the refrigerator.

Make the cake: Preheat the oven to 350 degrees F (180 degrees C). Line a cupcake tin with 12 cupcake liners. In a medium-sized bowl, mix the yolks, sour cream, and vanilla together.

In a separate large bowl, whisk the flour, caster sugar, baking powder, baking soda, and salt together until thoroughly combined. Add the butter, and, using a hand mixer or stand mixer, blend on medium speed until you get a sandy mixture.

Add half of the egg mixture into the bowl, and blend for 10 seconds until combined. Add the second half of the mixture, and blend for 20 seconds until completely smooth and thoroughly combined.

Scoop batter into prepared cupcake tins until 3/4 full. Scoop 1 teaspoon of the walnut filling into each cupcake tin. Using an offset spatula, fold the batter into the filling 2 to 3 times. Scoop around 2 to 3 teaspoons of the walnut crumble onto the tops of each cupcake tin. Lightly press down with your fingers. If using, press thinly sliced apple slices into each cupcake prior to topping with the crumble. 

Bake the cupcakes for 25 minutes until the tops are golden brown. Transfer onto a wire rack and cool completely. Serve with coffee for breakfast.