Base

Cup of Yum
1. Grease the slice tin (approx 28 x 18cm) and line with baking paper, leaving paper overhanging at sides to assist with removal of slice later.
2. Pre-heat oven to moderate (170-180 degrees celsius, fan-forced).
3. Cream butter and sugar.
4. Add egg and beat again for a minute or two until completely combined.
5. Add sifted flour and zest and mix until combined.
6. Press mixture into tin. Flour your hands if mixture is too sticky to work with.
7. Use the back of a metal spoon and a small glass jar to assist in evening out the mixture to form an even, flat surface.
8. Bake for 17-20 minutes or until lightly browned.
9. Allow to cool in tin.

Lemon Filling

1. Heat sugar, water and lemon juice in a saucepan and bring to the boil.
2. Combine cornflour with the 2 tablespoons water and blend to a paste. Add to saucepan and continue to boil rapidly, stirring from time to time, for 10 minutes or until mixture thickens.
3. Allow to cool to a lukewarm temperature and then spread over cooled biscuit base.
4. Place in fridge while you make up the top cream layer.

Cream Topping

1. Heat milk in a saucepan until bubbles begin to form around edges of saucepan.
2. Combine cornflour with the tablespoon of milk and blend to a paste. Add to saucepan and whisk over heat until mixture thickens. Remove from heat and add butter and icing sugar. Stir until combined.
3. Allow mixture to cool completely.
4. Whisk mixture and then spread over lemon filling layer.
5. Sprinkle shredded coconut over top of slice if desired.
6. Place in fridge for at least a few hours to set.
7. Remove slice from tin using overhanging paper and slice into squares.
8. Store slice in the fridge.