Preheat the oven to 160°C Fan/180°C conventional oven/355°F and grease and line 2 x 20cm loose-based round cake tins with non-stick baking paper. Set aside.

In a large bowl with a handheld mixer or stand mixer fitted with the paddle attachment, cream together the butter and sugar for about 3-5 minutes until lighter in colour and completely smooth. Add the vanilla extract and mix again.

Add the eggs one at a time, whisking until the batter is completely smooth.

In a food processor or blender, grind the pistachios into a fine crumb.

Sift in the flour and baking powder, then add the salt and ground pistachios. Fold in carefully until just combined.

Divide the batter equally between the two prepared tins and smooth over the surface.

Bake for about 35 minutes, or until well risen and a skewer inserted into the centre comes out clean. Cool in the tins for 15 minutes before turning out onto a wire rack to cool completely.

Meanwhile, prepare the buttercream by creaming together the butter and sifted icing sugar until pale and increased in size. Add the pistachio cream, salt, and lemon juice, and beat again. Adjust the lemon to taste.

Once the cakes have cooled, set one on a flat plate. Pipe half of the buttercream on top, then spread the raspberry jam evenly over it.

Top with the second cake and the remaining buttercream.

Decorate with fresh raspberries, sprigs of mint, and chopped pistachios. Enjoy!