Add sugar, water, and corn syrup to a heavy, medium sized saucepan. Heat over medium heat, stirring until just combined. Stop stirring and allow mixture to boil.
Cook until the mixture turns an amber color, 10-15 minutes. Watch carefully because caramel can go from lovely brown to stinky black in a heartbeat.
Remove from heat and add cream and vanilla (or seeds from 1 vanilla bean). Stir to combine. Be careful because the cream will be inclined to pop and splatter. It may seem like your caramel is siezing up but keep stirring and it will smooth out. Add in sea salt and stir to combine.
Enjoy now or store in a jar in the fridge for 2-3 weeks