For the pastry, combine the flour, olive oil, water and salt in a large bowl. Mix with a pastry scraper or your hands until it forms a smooth ball. Please do not continue to knead the pastry once it has come together. Wrap the pastry in plastic and set aside in the refrigerator for at least 30 minutes.
Bring a medium pot of water to a boil and cook the rice for about 15 mins. Drain and set aside.
Thinly slice the chard leaves and set aside.
Chop the onion finely and cut the bacon into small dice. In a large frying pan, heat the olive oil and sauté the onion and bacon over medium heat until the bacon starts to brown lightly. Add the chard and sauté for about 5 minutes. Transfer this mixture to a large bowl and add the cooked rice, 2 of the eggs, the grated Parmesan, salt and pepper.
Oil a large tart tin (28 cm, 11 inches). On a lightly floured surface, roll the pastry out as thinly as you can. Line the pan with 2/3 of the pastry, letting it hang over the edges of the pan. Fill with the vegetable mixture, fold the pastry's edges over the filling, and top with the remaining pastry, tucking it around the sides. Beat the remaining egg and brush the surface with it. Bake for 25-30 minutes, until golden. Serve warm or at room temperature.