Slice roughly about half of the strawberries into vertical slices and choose 20 best looking slices. Set them aside. Place all the remaining strawberries and off cuts to a blender together with lemon juice and mix to a smooth puree.
Transfer the strawberry puree into a small saucepan and bring it to boil. Cook for 5 minutes, over medium-high heat, stirring it often. Add 3 tbsp of sugar and cook again for another 5 minutes until you have thick puree. Transfer the mixture into a large bowl and allow it to cool.
In a meantime, preheat the oven to 160C (fan) and grease and line the baking tin (leave plenty of baking paper overhanging, as it will help to remove the bake from the tin later).
In a large bowl, mix the coconut with condensed milk until well combined. Transfer half of the coconut mixture to the bowl with cooled strawberry puree and add the pink food colouring gel (if using). Mix until well combined. Add 4 tbsp of milk to the bowl with remaining coconut and mix to combine.
Using an electric mixer, beat the egg whites with a pinch of salt until stiff peaks. Add the remaining caster sugar, 1 tbsp at a time, whisking well between each addition, until glossy. Fold half of the meringue into each bowl with coconut mixture.
Place the strawberry coconut mixture in the baking tin and spread it with the spatula to level it out. Put in the oven and bake for 10 minutes. Take out of the oven and gently spoon the white coconut layer on top. Top with slices of strawberry (4 rows of 5) and sprinkle small pinch of extra sugar on top. Bake for 40- 45 minutes or until pale golden, just set and risen. Cover the bake with kitchen foil if it starts to catch the colour too much. Take out of the oven and allow it to cool for 10 minutes in the tin. Use the overhanging baking paper to carefully lift the bake from the tin onto a wire rack and leave it to cool completely before cutting into squares. Enjoy!