Butter the inside of glass baking dish or line with parchment paper and butter paper.

In a large sauce pan over medium heat, mix the Sugar, Corn Syrup and Evaporated milk.. Stir regularly. Mixture will begin boiling. Reduce heat if it seems ready to boil over.

Continue cooking until mixture reaches soft ball stage (235-245 degrees). You can test for this by seeing the syrup forms a ball while in the cold water, but flattens once removed from the water.

Remove pan from heat and add butter and vanilla.

Stir until butter is melted and evenly distributed.

Add peanut butter and continue stirring until mixture start to lose it's sheen. Pour into the prepared dish to cool.