- Set aside half of the raspberries for the filling. Put the rest into a bowl with the icing sugar, and crush lightly with a fork. Cut the passion fruit in half, scoop out the pulp and stir into the crushed raspberries.
- Preheat the oven to 200°C (400°F, gas mark 6). Grease a 23 x 33 cm (9 x 13 in) Swiss roll tin and line the bottom with baking parchment.
- Put the eggs and sugar in a large bowl and beat with an electric mixer until very thick and pale, and the mixture leaves a trail on the surface when the beaters are lifted out. (If using a hand whisk or rotary beater, set the bowl over a pan of almost boiling water, making sure the water is not touching the base of the bowl.)
- Sift half the flour over the whisked mixture and gently fold it in with a large metal spoon. Sift over the remaining flour and fold in together with the tepid water.
- Pour the mixture into the prepared tin and shake gently so that it spreads evenly into the corners. Bake for 10–12 minutes or until the sponge is well risen and pale golden, and springs back when pressed gently.
- Turn out onto a sheet of baking parchment that is slightly larger than the sponge. Peel off the lining paper. Trim the crusty edges of the sponge with a sharp knife and make a score mark 2.5 cm (1 in) from one of the shorter edges (this will make the sponge easier to roll up).
- Spread the crushed raspberry mixture over the hot sponge, leaving a 1 cm (½ in) border all round. Scatter over the reserved raspberries. Carefully roll up the sponge from one of the short edges and place seam side down on a serving plate.
- Serve warm or cold, cut into slices. Decorate each serving with a few extra raspberries and a sprig of mint. Serve with custard, if liked.
Each serving provides
A, B12, C, copper
Some more ideas
For a wholemeal sponge roll, use 55 g (2 oz) plain wholemeal flour and 55 g (2 oz) plain white flour. * Instead of the raspberry and passion fruit filling, spread the warm sponge with 5 tbsp of your favourite fruit conserve, warmed so that it will spread easily. * Make an apple, strawberry and hazelnut sponge roll. For the filling, put 225 g (8 oz) cooking apples and 225 g (8 oz) dessert apples, both peeled and finely chopped, in a saucepan with 1 tbsp orange juice. Cover and cook gently for 15 minutes, then remove the lid and cook for a further 5–6 minutes, stirring frequently, until most of the fruit juices have evaporated and the apples are thick and pulpy. Stir in 30 g (1 oz) caster sugar and 170 g (6 oz) sliced small strawberries. For the sponge, replace the flour with a mixture of 55 g (2 oz) each ground hazelnuts and plain flour. Bake, fill and roll up as in the main recipe. When serving, decorate with extra strawberries and sprigs of fresh mint.
Raspberries not only provide plenty of vitamin C (32 mg per 100 g/3½ oz), they also contain vitamin E, both of which are powerful antioxidants.