For the pastry, sift the flour and cayenne pepper into a bowl. Add the margarine to the flour, and rub in, until the mixture resembles breadcrumbs. Add the water gradually until you have a smooth dough.
Roll out the pastry and line tins. Neaten the edges and bake blind (lined with foil and baking beans) in the pre-heated oven for about 15 - 20 minutes
Remove and turn the oven up to 200c / 400f / GAs 6
Peel the potatoes and cook in boiling water for about 15 - 20 minutes. Drain and mash the potatoes until very smooth, then add the margarine
Peel the onions and carrots. Trim courgette, deseed peppers. Dice all the vegetables into small pieces, and sweat to soften in little olive oil
Pour the baked beans into the flan case then layer the vegetables over them. Finally smooth the potato on the top. Sprinkle a little grated cheese over the flan