Estonian Strawberry Roulade (Berry Swiss Roll)

I'm not claiming that Swiss Roll or Strawberry Roulade is by any means unique to Estonia. But I guess our most popular version of the roll - filled with a mixture of curd cheese and whipped cream, as well as berries, is rather typical and perhaps less common outside the country. Here's how I make it.

* If you live in the UK, try the Polish shops for 'tvorog'. In the US, some of the farmer's cheese look and taste very similar to our curd cheese (or buy 'tvorog' from Russian shops). In Finland, use 'rahka' and in Sweden 'kesella'. Alternatively, try ricotta, but add a spoonful or two of sour cream and a squeeze of lemon juice to make it more similar to curd cheese.

Strawberry Roulade
(Rullbiskviit maasikate ja kohupiimakreemiga)
Makes about 10 slices



Sponge:
4 large eggs
100 g caster sugar
55 g plain/all-purpose flour
50 g potato starch/potato flour
1 tsp baking powder

Filling:
200 ml whipping cream (35%)
1 Tbsp caster sugar (or vanilla sugar, if you prefer)
250 curd cheese
300-400 g fresh strawberries

Garnish:
icing sugar
fresh mint or lemon balm (optional)

Make the sponge: whisk eggs and sugar until very thick, pale and foamy (this would take about 8-10 minutes or slightly less, when using a KitchenAid). Mix flour, potato starch and baking powder in a measuring jug, then pour through a sieve onto the egg foam. Using a wide spatula or metal spoon, gently stir until just combined.
Spread the batter onto a oven sheet covered with baking paper.
Bake in a preheated 225 C / 437 F oven for about 7-8 minutes, until the sponge is light golden brown on top. IT IS IMPORTANT NOT TO OVERCOOK THE SPONGE, AS IT WON'T ROLL NEATLY WHEN YOU BAKE IT FOR TOO LONG!
Take the sponge out of the oven.
Place a clean sheet of baking paper onto your work surface and sprinkle with some caster sugar. Carefully flip the cooked sponge onto the baking paper, upside down. Now peel off the "baked" baking paper, then replace on top, cover with a kitchen towel and leave to cool.
To make the cream, whip the cream and sugar until soft peaks form. Then fold in the curd cheese, whisking again lightly to combine.
Wash and dry the strawberries, then hull and cut into slices.
Remove the kitchen towel and the "baked" baking paper from the sponge cake.
Spread the curd cheese cream onto the cooled sponge cake, leaving about 2 inches/5 cm of one of the long edges clean. Scatter strawberries on top.
With the help of the baking paper, roll tightly into a roulade, starting from the long edge covered with cream.
(You can put the undecorated roulade into the fridge for up to 24 hours, wrapped in clingfilm or parchment paper. It will be easier to cut into neat slices, when allowed to rest in the fridge for a while).
Decorate with fresh strawberries and some mint or lemon balm leaves, dust with icing sugar and serve.