First, make the pastry. Place the ingredients in a bowl and rub together between your fingers until you get a breadcrumb-like consistency. Bring this together into a dough, adding a splash of water if the mix is too dry. Wrap in cling film and refrigerate until you're ready to use it.
For the curd, peel, core and chop the apples into 1cm pieces. Place them in a pan with the water, salt, lemon zest and juice and the sugar. Bring to the boil, stir until the sugar has dissolved and high simmer for 20 minutes, or until the apple has completely softened. Stir the cornflour into the soya milk until lump free, then stir into the apple mix.
Cook for a further 5 minutes to thicken the curd,
then stir in the sunflower spread and turn off the heat.
Preheat your oven to 200�C (gas mark 6). Roll out your pastry on a floured surface then use it to line a 23cm tart tin. Prick the base and blind bake it for 10 minutes. Set aside.
For the meringue, put the chickpea liquid in a stand mixer with the cream of tartar. Whisk on high speed for five minutes, or until peaks form when you pull the whisk out of the mixture. With the mixer still running, gradually pour in the sugar, then add the vanilla extract. Whisk again until the mixture is nice and stiff.
Briefly reheat your curd so it's nice and hot, then pour it into the pastry case and spread evenly. Gently spoon the meringue over the curd so the pastry edges are covered and swirl it around to create peaks. Bake for 20-25 minutes until the meringue is golden on top. Leave to cool before serving.