LEMON FILLING

1. Combine the tapioca flour/starch, salt, flour, sugar and water in a medium saucepan.
2. Simmer over medium-low heat until the mixture thickens, while continually stirring. Remove from heat.
3. Pour about 1/2 cup of the thickened mixture over the beaten egg yolks and whisk together quickly. This process tempers the egg yolks so that they do not scramble.
4. Pour this mixture back into the pot and whisk it in quickly. Return the pan to the heat and continuously stir for a few minutes until the mixture is thick and evenly smooth.
5. Whisk in the lemon juice and zest and remove from the heat.
6. Finally, whisk in the butter and set aside to cool while you prepare the crumble mixture.

CRUMBLE

1. Preheat oven to 180C
2. Mix the flour, sugar, baking powder, coconut and salt.
3. Use your hands or a pastry blender to cut in the butter until you have coarse crumbs.
4. Press half of the crumb mixture into the bottom of well-greased small round tartlet tins or one large (9 x 13 inch) round quiche tin.
5. Pour the lemon filling evenly over the bottom crumbs.
6. Gently sprinkle the remaining crumbs over the lemon filling and press down gently.
7. Bake in a 180C oven for 40 minutes or until almost light golden brown.
8. Remove and add toasted coconut chips, press down gently with a spatula. Then return to the oven and bake for a further 2 minutes.
9. Cool completely in the tin. Lightly dust with icing sugar and serve.