Gently warm ½ cup dark rum and ¾ cup raisins in a small saucepan over low heat until just starting to steam. Remove from the heat, cover, and steep for 20 minutes. Drain the raisins, reserving both the rum and raisins. Prepare Vanilla Ice Cream, substituting 1 tablespoon of the rum for the vanilla or vanilla bean. When the ice cream is almost frozen, add the raisins.