Preheat the oven to 425F. Combine the flour, water, olive oil and salt in the bowl of a food processor until the mixture forms a ball. Remove dough and knead until very soft. Place the Swiss chard in a flameproof casserole or Dutch oven and sprinkle with a pinch of salt. Cook over a low heat until softened, stirring occasionally. Drain and place the Swiss chard in a dish cloth. Squeeze hard to remove all the excess water. Place the Swiss chard in a mixing bowl and add 4 of the beaten eggs, the cheese, nutmeg, salt and pepper. Roll out the pastry and cut into 2 10-inch circles. Grease a cookie sheet and place one of the pastry circles on it. Spoon the Swiss chard mixture onto the pie crust leaving a 1/2-inch margin around the edges. Brush the edges with the remaining beaten egg. Place the remaining pastry round over the filling and press the pastry edges together with your fingers. Make a hole in the center of the pie and place a rolled up piece of foil in it to allow steam to escape. Brush the pie surface with beaten egg. Bake for 55-60 minutes, until golden brown.
