First of all, Vintage Port is not the most popular port after eating in Portugal, but Tawny port.
Tawny Port actually starts as a Ruby Port, but then takes a long period of time in the cask to soften the port and give its round character. The large oak barrels are somewhat porous, which causes oxygen to evaporate over the years. This concentrates flavors in the remaining port and leaves a slight "air gap" at the top of the barrel. Through this air, the Tawny Port can oxidize during its time in the oak barrel. Because this oxidation process takes place, the color of the wine slowly changes from a purpleish color to a Tawny or reddish-brown color. The more time the Tawny spends in wood, the more the taste and color of the Tawny becomes more complex.
Unlike Vintage Port, Tawny Port is often served lightly chilled or even poured over ice. Lightly cooled Tawny port ensures a beautiful summer drink.
Tawny Port pairs well with: various dried fruits (especially apricots), cream caramel, walnuts, pear cake, bread pudding, rice paper, strawberries, lightly heated and sprinkled with vanilla ice cream, crisp cheddar cheese, cream brûlee or bitter sweet chocolate desserts.