In heavy saucepan, combine sugar and soda; stir in remaining ingredients in order listed, except vanilla and pecans. Place over medium heat and bring to boil; reduce heat to low and simmer for about 10 minutes, stirring often. Remove pan from heat and immediately stir in vanilla and pecans. Cool.
May serve lukewarm over ice cream, pound cake, or cheesecake, or even bread pudding. Sauce will thicken as it cools.
Louisiana Pecan Growers Association