Combine sugar, corn syrup, water, and salt, in nonstick saucepan
Bring to a full boil, then add peanuts, cook until the syrup begins to turn color
Add butter and vanilla. Cook until amber colored and continue cooking slowly until it is 300 ̊ using a candy thermometer, stirring occasionally
Remove from heat and add baking soda, stirring well!
Pour immediately onto prepared nonstick pack with silicone or parchment or a buttered hard surface (marble, porcelain) or baking sheet
Cool and spread out until very thin, break into pieces