Preheat the oven to 350°F (180°C). Grease your cake tin (in this case we’ve used 3 shallow 8 inch/20cm tins; but you can use a deep one and then just slice it after baking) and set aside.
In a large mixing bowl, place the softened butter and sugar, then beat together until pale.
Add the rest of the ingredients and continue beating until the mixture becomes smooth.
Divide the batter between each cake tin, gently smoothen the tops.
Bake for 25 minutes. If you’re not sure whether it’s ready, insert a skewer - if it comes out clean, it’s done!
Don’t remove the tins until the sponge is cooled down a bit, 10 minutes should be enough. Remove the cake from the tins and transfer to a cooling rack.
You’ll need an electric mixer for this one. Place the mascarpone and salt in a large mixing bowl. Mix it together on low speed.
While the motor is running, pour in the cream - slowly, gradually, not all at once. Then increase the speed a bit and start beating in the sugar. Continue until you see “blobs” forming.
This should make around 4 cups of creamy deliciousness. Set aside around two thirds of it - you’ll need it for the cake's filling.
Add food colouring to the remaining ⅓ of the cream. A few drops should be enough. Use the mixer on medium setting and give it a good mix.
Once the sponges are cooled, lay one with the topside down on a cake stand. Spread with a half of your "white" mixture. Top with another sponge (topside up this time) and push down gently. Spread another half of the white cream and top with the last layer of the cake.
Ice the top of the cake with the pink mascarpone mixture by piling it in the centre. Then spread it to the sides, then gradually bring it down the sides. Smooth with a spoon (or a palette knife if you have one).
Last, but not least - use a green icing marker to write "Happee birthdae" and the name of the Birthday boy or girl.