Serves: 8 to 10
110g plain flour
1 tsp baking powder
1⁄4 tsp salt
1 tsp ground caraway seeds
30ml whole milk
3 eggs, separated
110g caster sugar
30g icing sugar
For The jam (optional)
125g fresh raspberries
125g caster sugar
Juice of 1⁄2 lemon
For The Filling
185ml heavy cream
11⁄2 tsp icing sugar
75g chestnut puree
1 tbsp icing sugar
1 tbsp cocoa powder
Preheat the oven to 200°C.
Grease a rectangular spring form cake tin (25×31cm) and line with parchment paper. If you do not have a spring form tin, cut the edges of the parchment paper to extend 5cm above the sides of the tin.
Sift together the flour, baking powder, salt, and ground caraway in a medium bowl. Set aside.
Warm the milk in a small saucepan over medium heat. Remove from the heat and set aside.
Use an electric mixer on medium speed to whisk the egg whites to soft peaks in a medium bowl. Gradually add one tablespoon of sugar and whisk well, then repeat with the remaining sugar. Add the egg yolks 1 at a time, whisking until well combined. Continue whisking until thick and glossy, about 5 minutes.
Pour in the warm milk and spoon the flour mixture over the top. Fold the mixture together with a rubber spatula until just combined. Gently spread the mixture in the cake tin. Smooth and level the surface with a palette knife or the back of a spoon.
Bake for 8 to 10 minutes or until a toothpick inserted in the center of the sponge comes out clean. It should be lightly golden and springy to the touch. Remove from the oven and set aside to cool for 5 to 7 minutes.
Place a fresh piece of parchment paper a little larger than the sponge on your work surface. Sift the icing sugar evenly over the paper. Turn the sponge out on top of the sugar. Remove the parchment paper that lined the base of the cake tin. Working from a short edge, roll up the sponge carefully with the fresh paper, so the cake does not stick to itself. Set aside on a wire rack to cool completely at room temperature.
If desired, prepare the jam by placing the raspberries and sugar in a small saucepan over medium-low heat and stir for a few minutes, until the sugar has dissolved. Stir in the lemon juice. Increase the heat and bring to a vigorous boil. Heat the mixture to 105°C, using a candy thermometer to check for accuracy. To confirm whether it is ready, place a teaspoonful of the jam on a cold plate. Push it gently with your finger; if it wrinkles slightly, it will set when cool. If wrinkles do not appear, leave the jam over the heat for a few more minutes, then test again. When it is ready, pour the jam into a clean bowl and set aside until it has cooled completely at room temperature.
To prepare the chestnut cream filling, use an electric mixer on medium speed to whisk together the cream and icing sugar to medium-firm peaks in a medium bowl. Fold in the chestnut puree with a rubber spatula, and combine well.
Unroll the sponge and discard the parchment paper. Spread the cooled raspberry jam evenly over it, if desired. Spread the chestnut cream on top and roll up the cake again. Cut off about 1 cm from each end of the roll to make an even presentation.
Before serving, dust with icing sugar and cocoa.