Spinach Flan

For the pastry:   8oz plain flour  
                         4oz Margarine
                         Cold water to mix.
For the filling:   3 large eggs
                        1/4pt milk
                        12 oz cooked spinach
                        6 oz cheese
A  10-inch flan ring

First make the pastry:   Sift the flour in a bowl, add the margarine cut into small pieces and rub till they                  
                                     resemble fine breadcrumbs. Stir in enough cold water to make a fairly stiff dough.  
                                   Leave to rest.
                                     Turn the dough into a floured ring and line the tin, and leave to rest.
For the filling:   Beat the eggs together,then gradually add the milk.  Put the spinach into a saucepan stir
                        in the milk and eggs and crumble the cheese. Check the filling for seasoning before
                       pouring into flan ring.
                       Bake the Spinach Flan on the centre shelf of a moderately hot oven gas mark 5 or 375
                       degrees for thirty five to forty minutes until the filling is set.
                       Serve the flan hot, cut into pieces. Divide the slices . Garnish the centre  with half a lemon