Reduce oven to 300 and place baking dish full of hot water on the bottom rack to create moisture (leave this in while baking).
Beat cream cheese, sugar and vanilla with electric mixer on med until light and fluffy, about 30-60 sec.
While beating on low add the caramel sauce
Scrape the bowl, beat 45 sec more - make sure it's smooth with no chunks.
Lightly whisk the eggs and yolks together and add to cream cheese mixture
Mix on low speed until they are incorporated and the batter is velvety, about 30 sec, scrape the bowl and mix 10 sec more - do NOT overbeat.
Pour the filling over crust, bake on the center rack about 1 hour +.
how to tell cheesecake is done - When you open the rack and shift the pan the center 3-4 inches will jiggle - not like soup, like a loose jello jigglers.
Turn the oven off and crack open the door and let the cake cool then refrigerate overnight.
The next day pour the rest of the caramel over the top of the cake
Sprinkle the fleur de sel over the top of the cheesecake, as much or as little (I'm all for MORE is better)
Cook the sauce while the crust is baking, then let it cool. When it's slightly cool press some plastic wrap down across the top so the sauce doesn't get a "skin". It will be slightly warm when you add it to the filling. You'll probably need to warm it up just a bit before adding it the top of the cheesecake so keep it in a microwave safe container.