Sweet, citrus-flavored and strong, orange liqueur can be sipped alone or added to cocktails. Orange liqueur gets most of its intense flavor from the peels of oranges. The alcohol dissolves the orange peel’s essential oils over a period of a few days. The resulting liqueur has all the bright citrus flavor of the orange without any pulp or a drop of orange juice. Select oranges that are free of blemishes and have bright orange peels. To preview the flavor of the liqueur, smell the oranges as you squeeze them gently to release the essence of the oils.
Rinse 6 to 12 oranges in cold, running water and pat them dry with a clean kitchen towel. Rinse one-half a lemon or lime to give the liqueur a tart edge, if you wish.
Peel away the thin outer zest of the oranges with a vegetable peeler or citrus zester. Press lightly as you peel to avoid cutting away any of the orange's white pith. The peels should be so thin you can see light through them.
Slide the sliced peels into a glass jar, and pour in 2 cups of vodka or other neutral spirits. Seal the jar securely.
Place the sealed jar in the refrigerator, and allow the peels to soak for at least two weeks. Shake the sealed jar for 3 seconds each day, and then return it to the fridge.
Remove the sugar water from the heat, and allow it to cool, uncovered, for 30 minutes.
Remove the lid from the glass jar, and cover the opening with a piece of cheesecloth that has been folded to be 4 layers thick.