Duck à l’orange is a French sweet and sour dish, which is unusual in classical French cooking. It is duck served with an orange sauce.
Larousse Gastromique (1971) allows two classical methods. Both call for bitter, Seville oranges.
In the first method, you braise a duck, drain, carve and slice, and arrange the pieces on a platter.
You serve this with a Sauce Bigarade, made like this: Brown 2 teaspoons of sugar, then mix in 3 tablespoons of wine vinegar and simmer a bit to thicken. This first stage is called a “gastrique.” Then add the braising juices from cooking the duke, then simmer this all down. Then add the juice of 1 bitter orange and 1/2 lemon. Simmer to reduce again, then strain. Julienne the rind of the orange and the 1/2 lemon. Blanch the rind, drain, add to sauce. Pour sauce over carved duck; serve.
As a second, older method, Larousse indicates to pan fry the duck, remove it from pan, add some veal stock (“blond de veau”) or demi-glace sauce, then use this in place of the braising juices in proceeding as above. This older method requires more work, as the “blond de veau” or demi-glace sauces are work in themselves to prepare first.
Modern methods that simplify the work even further include techniques such as roasting the duck, and making a sauce based on a roux, skipping the gastrique and adding an orange liqueur such as Cointreau to bolster the orange flavour.
Some people feel that it was Duck à l’Orange that helped to popularize French cooking in America in the 1960s.
Duck à l’orange, aka Duckling à l’Orange, aka Caneton à l’Orange, properly known in French as “Caneton à la Bigarade.”
The French word for duck is “canard”, but in cooking, it’s referred to as duckling, “caneton.”
“Bigarade” is French for Seville oranges.