This is another personal favorite. It is popular enough to be found in better grocery stores.
This cheese is made from dairy cattle concentrated on a 200-square-mile area in Holland called the Beemster Polder.
Beemster XO is the most mature cheese in the line. It is made from pasteurized milk and aged a minimum of 26 months. As with other Dutch-style cheeses, age confers heightened aromas and bigger flavors.
Inside, the paste is hard and the color of pumpkin, dotted with the tiny white flecks that indicate the presence of protein crystals. Over time, Beemster XO develops aromas of butterscotch, caramel and whiskey. On the tongue, it is creamy. The flavor is concentrated, malty and mellow.
This is a good link with a lot of information about this cheese.