Preheat your oven to 180C.
Grease a square baking tin (around 21cm x 21cm would work well)
Rub together the gluten free flour, 110g of sugar & the dairy free hard margarine until it forms a breadcrumb consistency.
Add 1 egg and the vanilla extract to the bowl & mix until it forms a dough like consistency. (I used an electric whisk for this)
Bring together the dough into a lump with your hands. (I found mine was a little sticky but resist adding extra flour)
Press the dough into your prepared baking tin evenly and bake in the oven till slightly golden.. this will take about 15 minutes. (I pressed it in with my hands!)
After 15 minutes take the baking tin out of the oven and put to one side.
Whisk together the 2 remaining eggs & the other 110g of sugar.
Stir in the desiccated coconut.
Spread your pineapple jam all over your base. (I put mine on when slightly warm which worked well!)
Spread your coconut mixture over the jam.
Put it back in the oven for a further 20 minutes or until golden.
Allow to completely cool in the baking tin before removing and cutting into slices.
Enjoy!