With a fine grater, zest, then juice the orange.
With the flat side of a knife, press firmly on the cardamom pods to bruise them. In a large pot (not aluminum), combine zest, juice, cardamom, cloves, allspice, peppercorns, cinnamon, wine, sugar, and brandy. Cook over medium heat, stirring, until sugar dissolves, 1 to 2 minutes.
Reduce heat to low; simmer until flavors have melded, about 30 minutes. Pour through a fine-mesh sieve; garnish with cinnamon stick, if desired. Serve immediately.