Spray a 5 x 9-inch loaf pan with cooking spray and line it with waxed paper, folding the corners up.

In a microwave-safe bowl, combine unsalted butter and heavy cream. Heat in 30-second increments until melted. Let it cool slightly.

In a medium saucepan, combine water and light corn syrup. Add white sugar and stir gently to combine.

Bring the mixture to a boil over medium heat without stirring, then cover and simmer for one minute.

Remove the lid and continue boiling for 5 to 8 minutes without stirring until it reaches 320 degrees F.

Slowly add melted butter and cream mixture in increments, stirring until fully combined. Watch for foaming.

Continue cooking for another 5 to 8 minutes until the temperature reaches between 240 to 245 degrees F, for chewy or firmer caramels.

Carefully pour the caramel into the prepared loaf pan and sprinkle sea salt over the top while it's still hot.

Let the caramel cool at room temperature for about three hours, or refrigerate for one hour for a firmer texture.

Transfer the caramel slab to a cutting board and slice it into cubes of about 1/2 to 3/4 inch.

Cut small squares of waxed paper (approximately 3 inches each) to wrap each caramel.