light brown sugar, firmly packed
light corn syrup
- In a medium saucepan combine sugar, syrup, and butter.
- Cook, stirring constantly, over medium heat until sugar has dissolved and mixture comes to a full rolling boil. Allow to boil, without stirring, for exactly 1 minute; remove from heat and let stand for 5 minutes.
- In another bowl or large measuring cup, combine evaporated milk, baking soda, and vanilla. Stir into the slightly cooled sauce.
- Pour into jars, cover, and refrigerate.
- Place jar in a pan of warm water to reheat.