Preheat oven to 350 degrees F. In a large bowl fit with a mixer, cream together butter and both sugars. Add vanilla extract and salt. Slowly add flour, 1 cup at a time until incorporated. Mix for an extra minute or two. Roll dough together in a ball and place in the center of a floured surface. Roll dough out to 1/2 inch thick. With a circle cookie cutter or glass cup, cut out cookies and place on a greased cookie sheet. Bake in oven for 14-16 minutes. I baked mine for 14 minutes but do not over bake. It will depend on the size of the cookies. I used a small cup to cut the cookie shape. Removed and place on a cooling rack.
Meanwhile, make the nougat glue to hold it all together. In a small bowl combine 3/4 cup powdered sugar and a few drops of water and whisk to combine. This is used to hold the cookie and peanut butter nougat together. Spread in the center of cookie before adding nougat. To make nougat, combine marshmallow fluff, powdered sugar, peanut butter and peanuts in a stand mixer and mix until dough forms. You want to have a dough is not sticky and is not dry. If too sticky, add powdered sugar. If dry, turn mixer back on and add more peanut butter. You'll need parchment paper to roll the nougat dough. Place 1/2 the dough between sheets and using a rolling pin, roll nougat dough out to 1/4 - 1/2 inch thick. Using the same cookie cutter as before, cut dough then use a spatula to carefully remove and place on top of cookie.
Once cookies are cool, melt caramel and evaporated milk according to instructions on the bag. On medium heat, melt caramel. Once it starts to melt down, turn down to low and allow to melt. Using a spoon, pour a small spoonful of caramel over the center of the cookie and spread it to the edges with the backside of the spoon. Allow caramel to cool, I placed mine in the refrigerator for about 10 minutes to set.
To make the chocolate topping, melt chocolate in a small microwavable dish. Place chocolate chips and shortening in dish and place in microwave. Melt for about 2 minutes on POWER LEVEL 4, stirring the chocolate in between to smooth out. Chocolate chips will burn if power level is not set to 4. Using a butter knife, spread chocolate over the top of the cooled caramel.