Strawberry & white chocolate pistachio roulade

Line a 23x33cm Swiss roll tin with baking parchment. Place 50g pistachios and the flour in a food processor with a pinch of salt and whizz together until finely chopped.

Preheat the oven to 190ºC, gas mark 5. Place the sugar and eggs in a large bowl and whisk with an electric hand mixer until pale, voluminous and thick enough to leave a trail. Whisk in the green gel, if using.

Gently fold in the pistachio flour using a spatula, or large metal spoon, then pour into the prepared tin. Level the surface, then bake for 10-12 minutes until just firm to the touch.

Meanwhile, to make the filling, pour 75ml cream into a microwave-safe bowl and add the chocolate. Microwave on medium power for 60 seconds, then leave to stand for 2 minutes. Stir gently until smooth and shiny, then set aside to cool. If you don’t have a microwave, heat over a pan of just-simmering water.

Place a sheet of baking parchment onto a clean tea towel and dust with 1 tsp caster sugar. Turn the sponge out onto the paper, carefully peel off the baking paper and leave to cool.

Using the cleaned electric hand mixer, beat the soft cheese and remaining cream together until thick enough to hold its shape. Fold in the cooled chocolate mixture until smooth.

Trim the short ends of the sponge to help prevent cracking while rolling. Spread the cream mixture over the cooled sponge, leaving 1cm clear around the edges. Arrange the sliced strawberries over the top.

Using the paper to help, roll the sponge from one of the long sides to make a neat cylinder with the join underneath and move to a serving plate. Scatter with the reserved chopped nuts, then cover and chill until ready to serve. Finish with more halved strawberries here and there, if liked.