Preheat the oven to 180∞C and grease a tart tin (approx. 22cm) with 3 teaspoons of the butter and line a baking tray with parchment paper
In a large bowl, sieve in the flour and add the remaining butter
Rub the flour and butter together until you get a bread crumb consistency
Add the water and stir with a spatula until a dough forms, roll the dough together with your hands to create a ball and place it in the fridge for 20-30 minutes
For the Filling
In a large bowl add the butternut squash, pepper and courgette, olive oil, salt and pepper and stir to combined
Spread the mixed vegetables onto the baking tray and bake for 35-40 minutes, giving it little shake mid-way
Dust a clean counter top with a little gluten free flour, remove the dough from the fridge and roll out until it it’s wider than the base of the tin and ½ cm thick and carefully place in the tart tin
Brush the pastry with egg and blind bake in the oven for 8-10 minutes
Remove the pastry from the oven, add the cheese and then the vegetables
In a bowl beat the eggs, milk and beat, then pour over the vegetables
In a bowl beat the eggs, milk and beat, then pour over the vegetables