Line two large cookie sheets with parchment paper. Set aside.In a large bowl, or bowl of an electric stand mixer, mix butter and sugar together until creamy and combined. Add egg yolks and vanilla extract. Mix until combined. (Be sure to scrape the bowl every now and then to incorporate all the ingredients.)
Slowly add flour and salt to mixture. Mix until dough comes together and forms a ball. Scoop cookie dough out onto the prepared cookie sheets. 12 per cookie sheet. (I use a small cookie scoop).Press a small indent in the top of each cookie with your thumb; taking care to not make it too big or wide.Cover and refrigerate 1 to 2 hours to chill.
Preheat oven to 375 degrees F. Bake cookies 10 to 12 minutes or until lightly golden brown. Remove from oven and let cookies cool completely.
Once cookies are cooled, melt caramels in a microwave safe bowl, in 25 second increments. Carefully, pour one teaspoon of melted caramel in the hole of each cookie. Let the caramel set before topping with chocolate.Melt chocolate chips and shortening (or oil) in a microwave safe bowl, in 25 second increments. Drizzle one teaspoon of melted chocolate over each cookie. Let chocolate set before serving. Enjoy!