Boil brown sugar, molasses, cream and butter together, stirring all the time, until the sugar dissolves. Continue boiling without stirring until a soft ball is formed when a drop is placed in cold water.
Remove from the heat, add the vanilla extract and nuts, and stir the mixture until it begins to crystallize. Drop a spoonful of the mixture in small heaps on buttered baking sheets, leaving enough room between the pralines for them to spread slightly.
Makes: 4