Line a square 8x8 inches baking pan with parchment paper.
In a medium pot add the butter, cream, syrup, sugar and salt. Cook on medium/low heat, stirring constantly until it reaches 248F( 120C). Check with a cooking thermometer. It will take some time and you will see the colour change from a light brown to a dark brown.
When ready, remove the pot from the heat and gently stir in the vanilla, it might bubble so be careful.
Quickly pour the liquid into the prepared pan. Don't scrape the pot. Let the caramel cool in the pan for 30 minutes then sprinkle with seas salt or drizzle chocolate over it if desired. Cover the pan and refrigerate for 8 hours or overnight.
Remove the caramel from the pan, cut into squares and enjoy!
Notes
This homemade soft caramel recipe can be stored for several weeks in an airtight container in the refrigerator. They will become too soft if left at room temperature.They can also be stored in the freezer for a few months. Thaw before enjoying.