Peanut butter and jam marble cake traybake

Method

1. Heat the oven to 170°C fan/gas 5. Line the baking tin with baking paper. Put the 150g butter in a small pan and melt over a medium heat.
2. Put the melted butter, eggs, peanut butter, soured cream and sugar in a large bowl and mix using a rubber spatula until combined. Fold in the flour with a pinch of fine sea salt. Scrape a third of the mixture into a small bowl and stir in the jam.
3. Tip the non-jam mixture into the prepared tray, then add the jam mixture on top. Use a skewer or knife to lightly swirl the jam mixture through the rest until you get a marbled effect – but be careful not to overmix as you’ll lose the definition.
4. Bake for 22-25 minutes until golden and a skewer pushed into the centre comes out with just a few damp crumbs. Leave to cool in the tin for 5 minutes then transfer to a wire rack to cool completely.
5. For the icing, put the 100g butter and peanut butter in a bowl and beat for a few minutes with an electric mixer until creamy. Sift the icing sugar on top and add a pinch of fine salt, then beat at a medium speed until well combined. Add a splash of milk if needed to get it to an easily spreadable consistency. Use a palette knife to spread this over the cake with plenty of peaks and pockets for the jam.
6. Heat the jam in a small saucepan, then sift the 2 tbsp icing sugar on top and mix until combined. Allow to cool a little, then drizzle over the frosting and scatter with peanuts. Allow to set before cutting into squares to serve.