Knead the flour, butter, sugar and eggs together quickly. Make a ball of the dough and let rest in the refrigerator for at least one hour.
To prepar the filling: soak the grain for about a week, changing the water every day. Drain and boil with fresh water for 15 mins. Drain and put back in the pot with milk, lemon rind, cinnamon, vanilla, a pinch of salt, and 1 tbs. of sugar. Bring to a boil, lower and cook over low heat until the milk is absorbed. Remove and discard the lemon rind.
Sift the ricotta into a mixing bowl. Add the sugar and beat until creamy. Add the 2 yolks, the whole-wheat grain, diced candied fruits, grated lemon peel, and the orange-flower water. Fold in the beaten egg whites.
Grease a 12-in. baking pan with butter and dust with sugar. Line with 3/4 of the pastry. Roll out the remaining dough and cut into strips. Arrange the strips over the filling in a lattice design. Brush the strips of dough with egg yolk. Heat the oven to 375ºF and bake the cake for 1 1/2 hours, until the filling has set and the crust is golden brown. Sprinkle with confectioner's sugar before serving.
Note:
Pastiera is best if eaten a day after it is cooked, and it keeps in the refrigerator for a week. In Italy, grain is sold pre-cooked and softened, sealed in plastic bags.
