Add sugar and water to a medium to large saucepan, do not stir.
Heat over low heat until the sugar melts.Increase the heat to medium-high and allow the mixture to boil for 5 to 10 minutes, gently swirling the pan occasionally, until the mixture turns a medium amber caramel color.
At this point turn the heat to low and remove the pan from the burner.Slowly add the cream, vanilla, and Fleur de Sel and stand back. The mixture will bubble.
Return the saucepan to the burner and whisk the mixture until smooth. Continue to cook over low heat for 1 to 2 minutes.
Pour into a heat proof container and allow to cool at room temperature for several hours. The caramel will thicken as it cools.
