Whisk together the milk, flour, egg, sugar, and nutmeg in a small bowl until frothy and refrigerate for at least 1 hour. Meanwhile, cut away the rind and membranes of the orange so that only the fruit flesh remains. Chop the orange flesh into small pieces.
1/2 cup milk, 1/3 cup all purpose flour, 1 large eggs, 4 1/2 tsp sugar, 1 dash nutmeg, 1 small orange
When the batter is ready, melt the margarine in a small skillet over medium heat, rolling the skillet to completely coat it with the margarine. Using a small ladle, pour approximately 2 tablespoons of batter into the heated skillet, again rolling the skillet to quickly coat the bottom.
1 tsp unsalted butter
Using a plastic flexible spatula, turn the crepe when the edges begin to brown slightly. Cook the other side until it is also light brown. Remove the crepe from the pan quickly, fold it into quarters, and place it on a cool plate. Repeat until all the batter is used.
Mix together 1 tablespoon of the orange juice with the cornstarch until smooth. Return the small skillet to the heat and add the remaining orange juice and orange pieces, cooking until bubbly. Quickly add the cornstarch mixture and stir constantly with a wooden spoon.
1/4 cup unsweetened orange juice, 1 tsp cornstarch
When the mixture begins to thicken slightly, add the vanilla and stir well. Gently add the folded crepes back into the skillet, and swirl the skillet to coat the crepes with the sauce. The sauce should be slightly thickened, just enough to coat a spoon. (Add a mixture of another 1/2 teaspoon cornstarch and 1 teaspoon water if needed to further thicken the sauce.)
1/2 tsp vanilla
When all the crepes are thoroughly heated, divide the contents of the skillet onto two serving plates, top each with sour cream, and serve. If you like, before removing the crepes from the heat, turn the heat to high, add 2 tablespoons Gran Marnier or brandy, and flame before serving.
1 tbsp sour cream
Notes
Give the usual a day off and cook some crepes for brunch. Countless fillings that just add to the fun.