1. To make the fruit filling, place half the raspberries and the icing sugar in a bowl and crush lightly with a fork. Stir in the passion fruit pulp.
2. To make the sponge, preheat the oven to 400ºF (200°C). Grease a 30 x 20 cm (13 x 9 in.) Swiss roll pan and line the bottom with parchment paper.
3. Place the eggs and sugar in a large bowl and beat with an electric mixer until the mixture is very thick and pale, and leaves a trail on the surface when the beaters are lifted out.
4. Sift half the flour over the mixture and gently fold in with a large metal spoon. Sift over the remaining flour and fold in together with the tepid water.
5. Pour the mixture into the prepared pan and shake gently to spread it evenly into the corners. Bake for 10–12 minutes or until the sponge is well risen and pale golden, and springs back when pressed lightly.
6. Turn out onto a sheet of parchment paper that is slightly larger than the sponge. Peel off the lining paper. Remove the crusty edges of the sponge with a sharp knife and make a score mark 2 cm from one of the shorter edges all the way along.
7. Spread the raspberry and passion fruit filling over the hot sponge, leaving a 1 cm border all around. Scatter over the remaining half of the raspberries. Carefully roll up the sponge, starting from the edge with the score mark. Place the sponge roll, seam-side down, on a plate.
8. Serve raspberry and passion fruit sponge roll warm or cold, cut into slices. Decorate each serving with a few extra raspberries and a sprig of mint.

PER SERVING

194 calories
6 g protein
3 g total fat
1 g saturated fat
94 mg cholesterol
36 g total carbohydrate
23 g sugars
5 g fibre
28 mg sodium

Passion fruit offers one of the highest fibre counts of any fruit. In addition, it supplies moderate amounts of vitamin C and riboflavin and the minerals potassium, magnesium and zinc.