In a medium saucepan, combine 1 1/2 cup granulated sugar, 1 cup Karo syrup, 1/2 cup water, 1 pinch salt & 1 tbsp unsalted butter. Place over medium-high heat and allow it to boil. Add a candy thermometer.
Continue boiling & stirring mixture until it reaches Hard Crack temperature (300 degrees)
Quickly whisk in 1 tsp baking soda & 1 tsp vanilla. Be careful while stirring; it will expand.
Fold in 1 cup peanuts
Pour into a cookie sheet lined with parchment paper
Once cooled, crack into pieces and enjoy (cooling takes 1-2 hours)