To make the sponge, preheat the oven to 180 degrees Celsius (350 Fahrenheit).
In a large bowl, use a hand mixer to beat together the butter and sugar until you get a creamy texture.
Add the eggs one by one, beating well after each addition.
Sift in the flour, add the lemon zest and juice, and beat again.
Butter and flour 2 cake tins ( mine are 7.5 inches or 19 cm in diameter) and divide the batter evenly.
Bake for 20-25 minutes until the sponges are golden and a skewer inserted in the middle comes out clean.
Leave the sponges to cool down completely.
To make the buttercream, you can either use a hand mixer or a food processor.
Sift the icing sugar, add the butter and lemon juice and beat well until smooth.
Add the food colouring and beat again.
Once the sponges are cooled down, arrange one sponge on a cake stand, spread a quarter of the buttercream over, then top with the second sponge and spread the remaining buttercream over the top and sides.
Decorate with nicely piped buttercream swirls, mini chocolate eggs or any other decorations you like.