- 75g plain flour
- 2 tsp ground cinnamon
- 40g cold butter, chopped
- 40g brown sugar
- 2 tsp water
- Combine flour and cinnamon in a small bowl and use your fingertips to rub the butter into the flour until mixture resembles fine breadcrumbs.
- Add the sugar and water and stir until just combined.
- Spread the topping evenly over the cake batter before baking.