For the lemon curd filling

4 oz. unsalted butter, room temperature, cut into small chunks
6 oz. golden caster sugar
2 large juicy lemons, zested and juiced
1 tbsp. cornflour
2 eggs

For the cupcakes

2 oz. unsalted butter, softened
3 oz. caster sugar
1 lemon, zested
5 oz. self-raising flour
1 tsp. baking powder
¼ pt. milk
1 egg

For the buttercream

3 oz. unsalted butter, softened
9 oz. icing sugar, sifted
2 tbsp. lemon curd
couple drops of yellow food colouring (optional)
Edible sugar flowers (optional)

1. Make the lemon curd, by adding the butter, sugar, lemon juice and zest and the cornflour into a small pan. Set over a low-medium heat and start to melt the butter whilst stirring regularly. When the butter has completely melted, vigorously whisk in the eggs until fully incorporated. Whisk continuously for 10 minutes or until the mixture starts to thicken. Once it has thickened, immediately remove from the heat and pour the mixture into two medium-sized jars and seal with the lid. Place in the fridge to set.
2. Preheat the oven to 180º Celsius, and line a muffin tray with muffin sized paper cases.
3. In a mixing bowl, cream the sugar into the butter until pale and fluffy. Next cream in the lemon zest.
4. Sift in together the flour and the baking powder, then add the milk. Mix until you have a smooth thick batter.  Add the egg and continue to mix until everything is fully incorporated scraping the sides and bottom of the bowl as you go. 
5. Fill the paper cases with batter until about two-thirds full.
6. Bake the cupcakes for 18-20 minutes or until a toothpick comes out clean after being inserted into some of the cupcakes. Once baked, remove from the oven and leave to cool completely on a wired rack.
7. While the cupcakes are cooling, add all the ingredients for the buttercream into a clean mixing bowl and cream together with a wooden spoon. (Add more lemon curd if the buttercream is too stiff). Use an electric whisk to then fluff up the buttercream. Cover and set aside until the cupcakes are cooled.
8. Remove the cupcakes from the tray and then gently core the centre out of each cupcake.
9. Use a piping bag to fill each cupcake with the lemon curd. Alternatively use a teaspoon.
10. Fill a piping bag fitted with a Wilton 104 piping nozzle with the buttercream. With the thicker side of the nozzle touching the cupcake, pipe outwards towards the edge of the cupcake and then back into the centre. Repeat these strokes turning the cupcake round as you go. Pipe smaller petals on top using the same process but slightly less them halfway from the edges of the cupcake. Top with an edible flower or anything of your choice. (Alternatively, gently spread the buttercream with the back of a spoon).