In a medium-sized mixing bowl, use a wooden spoon to mix the eggs, flour and milk. Keep mixing, switching to a whisk if necessary until the mixture is homogenous. You can also use an electric mixer fitted with a whisk.
In an 8-inch frying pan over high heat, melt the butter, letting it cook until it foams. Gently pour the egg mixture in all at once and cook as you would a frittata, initially scrambling until the eggs begin to set, then letting the mixture settle across the pan and cook until the bottom side is golden brown. Add a pinch of sugar, a pinch of cinnamon, and half of the orange juice to the center of the frittata. Roll the frittata as you would an omelet, and lay in a baking dish. Dust with the remaining sugar, remaining cinnamon and douse with the remaining orange juice. Place in the oven and bake until the juice and spices form a golden crust, about 5 minutes. Slice into 4 portions and serve hot.