A recipe from Darryl McLean from Basils @297

Ingredients

• 250g butter, chopped, at room temperature
• 1 2/3 cups caster sugar
• 4 drops vanilla extract
• 3 eggs, at room temperature
• 2 1/3 cups self raising flour, sifted
• 300g light sour cream, at room temperature
• Zest and juice from ½ lemon
• Icing sugar, to serve

Filling

• ¾ cup lightly packed brown sugar
• 125g ground hazelnuts
• 1 teaspoon ground cinnamon

Method
Lightly grease 24cm cake pan, line base with baking paper.
For filling, combine sugar, hazelnuts and cinnamon in a bowl.
Beat butter, sugar and vanilla until pale and creamy. Add eggs one at a time, beating well after each and scraping down sides of bowl occasionally. Using a large metal spoon, gently fold in flour, sour cream, lemon zest and juice, until combined.
Spoon half cake batter into pan, smooth surface and sprinkle with half the filling. Spread half remaining cake batter over and sprinkle with filling. Spread evenly with remaining cake batter. Bake at 180C for 45-50 minutes, or until a skewer inserted in cake comes out clean. Cool in tin 5 minutes, then turn onto a wire rack to cool.
Serve dusted with icing sugar.