• Preheat oven to 350 degrees F.
• For cookies: in a medium bowl, combine butter and sugar, and beat with a hand mixer (or stand mixer) until light and fluffy, for about 3 minutes.
• Add in egg and vanilla, and beat until combined.
• Gradually add in flour, baking soda, and salt.  Mix on low until combined.
• Shape dough into a circle, flatten slightly, and wrap in plastic wrap.  Chill dough for at least an hour.
• Roll dough into 1 inch balls, and place on a baking sheet covered in parchment paper.  
• Use your thumb to push a deep well into the dough, being careful not to go all the way through to the baking sheet.
• Bake for 10-12 minutes.

For Caramel:

• In a small saucepan, combine brown sugar and butter, and cook over medium heat.  
• Bring to a boil, while occasionally stirring. 
• Boil for one minute, remove from heat,  and add whipping cream.  
• Stir to combine and allow to cool.
• Allow cookies to cool, and caramel has to cool.  
• Spoon caramel caramel into the “well” of the cookie.  
• Allow caramel to sit for about five minutes in each cookie, then sprinkle with salt.