In a medium bowl, combine flour, oil, eggs, egg yolks, and 1/2 cup milk, beating until blended and smooth. Add remaining milk, whisking until batter is smooth. Strain batter into a clean bowl. Refrigerate, covered, for 2 hours or longer. Melt the butter over low heat, and mix into the crêpe batter.
Heat a 7-inch non-stick skillet until a drop of water sizzles and rolls off. Pour in 2 tablespoons of batter, rotating pan to cover bottom of skillet evenly. Cook until lightly browned. Turn; brown slightly. Cool on rack. Stack crêpes.
Crêpes may be made ahead and refrigerated.
In a medium skillet, melt 1/4 cup butter. Stir in cup sugar, shredded orange peel and juice; cook over low heat, stirring occasionally, until peel is translucent, about 10 minutes. Add oranges, and 1/4 cup Grand Marnier.
In a small bowl, with an electric beater, cream butter with sugar until fluffy. Blend in Grand Marnier and orange peel. Use to spread on crêpes - about 1 tablespoon for each crêpe.
Fold each crêpe in half, then in half again. Arrange in pattern in orange sauce in a baking dish or skillet. Cook over low heat until sauce is hot and crepes are heated through. To serve: Bring crêpes to table right in baking dish or skillet. Gently heat brandy in a small saucepan just until vapor rises. Ignite with match and pour flaming brandy over heated crêpes. Serve with sauce.
CREPES CURACAO: Serve with cooked sliced peaches. Flame with curacao.
CREPES CAFOLA: Flavor batter with coffee extract and grated sweet chocolate. Flame with creme of cacao and Kahlua.
CREPES COPACABANA: Flavor batter with coffee extract and hazelnut puree. Flame with Kahlua.
CREPES HAWAIIAN: Serve with fresh sweet pineapple cubes.