Grease a 9x5" bread pan with nonstick cooking spray and line with parchment paper, leaving enough overhand on the sides to pull the caramels out later.
Spray with parchment paper with nonstick cooking spray and set aside.
Combine butter and heavy cream in a medium glass bowl and microwave for a minute and 30 seconds.
Stir and let butter melt.
Combine water and light corn syrup in a heavy-bottomed medium saucepan over medium heat. Add granulated sugar and stir.
Bring mixture to a boil and cover for 1 minute.
Remove lid and insert a candy thermometer.
Cook for 5-10 minutes, until candy reaches 320F.
Pour a small amount of the cream mixture into the candy and stir.
Continue adding the cream mixture a little bit at a time, stirring after each addition.
Cook until candy reaches 240F, about 5-10 minutes.
Pour candy quickly into the prepared pan and let cool for about 30 minutes.
Sprinkle with coarse sea salt and let cool for another 3-4 hours.
To serve, pull caramel out of the pan using the overhanging parchment paper and slice into 1" pieces.
ENJOY!!