* Line a 9x9 square inch square pan or pyrex with waxed paper, allowing for the waxed paper to hang over the edges.
* In a saucepan heat butter, heavy whipping cream, vanilla, whiskey, and 1/4 tsp. of salt to boiling, stirring frequently. After the mixture reaches boil, set aside.
* In larger saucepan (I used 3 qt.) mix sugar, water, and corn syrup to boiling over medium high heat WITHOUT stirring. Boil until sugar has turned a golden brown colour.
*When sugar mixture is done, turn off heat and SLOWLY add cream mixture. Be very careful as the mixture will rapidly boil up. Cook over medium-low heat until mixture has reached 248 F (firm ball) on candy thermometer. (It took my mixture a little longer than normal to reach this heat, but it usually takes between 10-15 min.)
*Spray waxed paper and pan with cooking spray and pour caramel into pan. Let cool for 10 min, then sprinkle with additional sea salt.
*Cool completely. (I put mine in the fridge for a bit.) After caramel has fully cooled cut into squares (or rectangles, or circles... it's up to you!)
** These caramels will remain somewhat tacky, so I wrapped mine in individual pieces with waxed paper. ENJOY!