Berry Berry Roll Cake - strawberries

Method

• I used a 30cm x 22cm (outside dimensions) sheet cake pan.
• You can also use a 26cm x 26cm pan.
• If the pan has a nonstick coating, lightly grease it with butter and refrigerate until you need it.
• If the pan is not non-stick, line it with a sheet of parchment paper.
• Cut 150 g of hulled strawberries into quarters, and put them into a small enamelled pan.
• Sprinkle the strawberries evenly with granulated sugar, mix lightly and leave to macerate for 10 to 15 minutes.
• As time passes, the strawberries will exude moisture as shown here.
• Start simmering over medium heat.
• When it starts to bubble, turn the heat down to low.
• Some foam (scum) will rise to the surface, but you don't need to remove it.
• After simmering the strawberries for about 3 minutes, add the lemon juice.
• Just a small amount, about 1/2 of a small teaspoon, is fine.
• After simmering for about 5 minutes, you should be able to clear the bottom of the pan when you drag a rubber spatula over it as shown here.
• When it reaches this stage it's done.
• Transfer the strawberry mixture to a container, and leave to cool.
• Make the batter.
• Put the eggs and sugar in a bowl and beat at high speed with a handheld mixer for 3 minutes, while holding the bowl over a pan of 60C or so hot water.
• After 3 minutes, take the bowl off the hot water, and beat at high speed for 4 minutes while slowly turning the mixer in a circle in the batter.
• The batter will become foamy and light colored.
• This is the batter when it's been beaten to the soft peak stage.
• It will be like soft fluffy marshmallow whip.
• Combine the cake flour and cornstarch, and sift 3 times.
• Add this in 4 batches to the batter, mixing between additions.
• (Use the handheld mixer switched off to mix.)
• When the flours are mixed in, beat on low speed for 30 seconds.
• We are now done with the handheld mixer.
• From here on we'll use a rubber spatula.
• Swirl the milk on the surface of the batter, add half the cooked strawberry puree and mix in quickly, repeatedly scooping the batter up from the bottom.
• When the puree is mixed evenly into the batter as shown in the step 15 photo, the batter will have less volume than before, but it's not a problem so don't worry!
• Pour the batter into the prepared cake pan, and tap the bottom of the pan 2 to 3 times on your work surface to remove any big air bubbles.
• (Don't overdo this!)
• Bake for 12 minutes in a preheated 180C oven.
• If a skewer stuck in the middle comes out clean the sponge is done.
• Don't overbake.
• Take the pan out of the oven, and immediately drop it with a bang on your work surface to push out extra steam.
• Cover tightly with aluminium foil, and flip over the pan with the foil side down onto a cooling rack.
• Take the pan off the sponge.
• The sponge will look like this.
• Cover with a sheet of kitchen parchment paper to prevent the surface from drying out, and leave to cool.
• Make the sheet of kitchen parchment paper large since it will be used later when rolling up the cake.
• While the sponge is cooling, make the cream filling.
• Put the heavy cream in a bowl and whip until creamy.
• Add the condensed milk and the rest of the strawberry puree, and whip the cream until peaks form.
• When the sponge has cooled down completely, flip it over again (the side with the strawberry bits will be on the bottom now) and take off the foil.
• Don't leave the sponge to cool for too long or it may crack.
• Slice about 2 cm of the edge that will be at the end of the roll diagonally.
• Cut the fresh strawberries to be rolled into the cake into quarters.
• Score the sponge in about 2cm intervals.
• The scores should be about 2mm deep.
• If you score the roll it will be easier to roll.
• Spread the cream filling on the sponge as shown, and put on the strawberries.
• Leave 4cm of the edge that will be at the end of the roll (the edge that was cut) clear of cream.
• Roll it up from the near side.
• Wrap up the rolled cake with the end side on the bottom in the kitchen parchment paper, and wrap again in plastic film and leave to rest in the refrigeratorfor 1 hour to finish.
• A strawberry filled roll cake.
• It's a sweet and sour cake packed with berries, limited to the strawberry season.
• If you cut the cake with a warmed knife, and wipe the blade clean of the cream filling after each cut, you can slice the cake very neatly.