Banana and Hazelnut Coffee Cake

Topping:90g plain flour
80g hazelnuts, finely chopped
120g light brown sugar
½ teaspoon salt
3 large ripe bananas
juice of 1 lemon
80g unsalted butter, melted

Cake:280g self raising flour
1 teaspoon baking powder
250g plain yogurt
1 teaspoon vanilla extract
90g unsalted butter, melted
150g caster sugar
2 large eggs

Preheat the oven to 180ºC/350ºF. Grease a 25cm square cake pan and line with baking parchment.
To make the topping, place the flour in a large bowl with the hazelnuts, sugar and salt. Pour over the melted butter, then mix with a round-bladed knife until it resembles rough crumbs. Chill until needed.
To make the cake, place all the ingredients in a large bowl and beat together until the mixture is smooth and thoroughly combined. Spoon into the pan and smooth with the back of a spoon.
Peel and slice the bananas, then toss with lemon juice in a bowl. Scatter the bananas evenly over the surface of the cake mixture, then sprinkle over the hazelnut topping.
Bake for 45-50 minutes, until a skewer inserted into the centre comes out clean. Cool for 10 minutes in the pan, then lift out. Serve warm or cold.
You can store it in an airtight container for 1-2 days.

Makes 16 squares