Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1      pound         light brown sugar
   1      cup           water
     1/2                medium-size peeled ripe
                        pineapple
   1      tablespoon    unsalted butter
   2      tablespoons   dark Jamaican or Puerto
                        Rican rum -- (or 1 teaspoon
                        vanilla extract)

Preparation:

Mix the sugar and water in a medium-size saucepan. bring to a boil over moderate heat, stirring once or twice to help the sugar dissolve. Boil 5 minutes. Remove from the heat. You should have 2 cups. Meanwhile, core the pineapple and cut into 1/4" chunks. You need about 1 1/2 cups. Melt butter in a medium-size heavy saucepan over moderate heat. Add the pineapple and cook 1 1/2 minutes, stirring occasionally, until the pineapple is hot. Add the rum or vanilla and let bubble 1 1/2 to 2 minutes. Add the brown sugar syrup and bring to a boil. Remove from the heat. Serve warm. The sauce keeps in the refrigerator at least a week. Source: Pancakes and Waffles by Elizabeth Alston