Preheat your oven to 175°C. Grease a 22 cm cake tin, so the parchment paper would stick, and line with parchment. You can also use two tins and divide the batter between the two, but keep in mind that the baking time will then be shorter.
In a big bowl, whisk your soft butter with an electric whisk until it is light and fluffy.
Add the sugar to the butter and whisk until very light pale. Take your time with this step as it can take several minutes to get the right structure.
Add the eggs one at a time to the butter-sugar fluff, so the batter would not split. Continue whisking until everything is incorporated.
Next, you can add the lemon and orange peel and vanilla extract to the batter, if you wish. I think it gives the sponge a nice extra taste. Mix until combined.
Carefully start folding in the flour into your batter. Do it slowly and in two or more steps, in order to not overmix the airy batter.
The batter should end up looking something like this.
Spread the batter evenly into your prepared cake tin and bake for about 30 - 35 minutes.
The cake is done when it is golden, springs back when touched and a skewer comes out clean. Leave it to cool in the tin.
When you are waiting for the cake to finish its cool down, it is a good time to whip up your whipped cream. I usually do not sweeten it too much as the cake is already pretty sweet. So do it according to your preference. You can also add some vanilla to the whipped cream if you feel like it.
Once the sponge has completely cooled, turn it out of the tin and cut into two equal layers.
Now, the assembly! My strategy was to first spread the lemon curd over the bottom layer. Then, I slathered on a rich amount of raspberry jam on top of the lemon curd and sprinkled on half of the fresh raspberries. On top of all that, I spread half of the previously whipped cream.
Then, put the other layer of cake on top and decorate with the rest of the whipped cream, fresh raspberries, strawberries, meringue kisses and a sprinkle of powdered sugar. The cake is best eaten fresh but it will stay for a day in the fridge. Enjoy!