Line an 8-inch square baking dish with aluminum foil and lightly grease it with butter.
In a heavy-bottomed saucepan over medium heat, stir together heavy cream, sugars and corn syrup. Stir constantly so sugar dissolves and doesn’t burn; it will be thick.
Bring mixture to a boil, and heat mixture to 245º F, stirring occasionally for 8-10 minutes. Mixture should be deep golden brown.
Remove pan from heat and season with salt, vanilla extract and butter, stirring continuously. Butter will cause mixture to spit and bubble, so be careful as you stir.
Once butter is incorporated, pour caramel into greased baking dish and sprinkle generously with sea salt. Let cool completely.
Once cool, lift caramel out of baking dish and peel away aluminum foil. Use a pizza cutter (lightly greased with non-stick spray, if desired), and cut caramels into squares or rectangles. Wrap with wax or parchment paper and store in an air-tight container.
Many years ago my husband was on a cruise and one of the ports was somewhere in Jamaica. He’d had these pies on the island and fell in love with them. He always spoke of them fondly so I went scouring the internet for a […]