1. In a large saucepan, combine syrup, cane sugar and water. Bring to a boil on high heat, then turn down, keeping boil going for 7 to 10 minutes or until mix turns a medium-brown/copper color.
2. While boiling, melt cream, butter and 1/4 teaspoon Frontier Fleur de Sel in another saucepan over medium heat.
3. Once the sugar mixture has turned color, carefully pour cream mixture into sugar mix, watching to ensure it does not boil over. (Combining the two will cause bubbling.) Continue to simmer the combined mix for 7 to 10 more minutes. The mixture will begin to thicken, similar to molasses.
4. Pour into well-greased 8x8-inch square baking pan. Let cool for 30 minutes. Sprinkle remaining Fleur de Sel over caramel. Let cool 3 to 4 hours and cut.
You can line the baking pan with parchment paper so when caramels are cooled you can pull entire piece out before cutting.