Step 1

Preheat oven to 375 degrees. Line a 9x13 pan with tin foil, leaving another overhang that you can use it like handles to pull it out.

Step 2

In a stand mixer, beat butter and shortening together until combined (about a minute). Add sugars and beat another minute or two. Add vanilla and egg. Beat again (I know, so much beating here. . . ).

Step 3

Mix in the chocolate chips.

Step 4

Add the flour, soda, and salt. Mix JUST until combined. It will look over-floured for a few seconds, but should come together fairly quickly.

Step 5

Press 2/3rds of the dough into the bottom of the pan. Bake for 8-10 minutes, until it's lightly set, but not very brown.

Step 6

Meanwhile, in a saucepan over medium heat, melt the caramels and peanut butter with the evaporated milk, stirring frequently, until smooth.

Step 7

When the cookie base is finished, remove it from the oven and pour the peanut butter caramel sauce over the top. Smooth it all the way to the edges. Sprinkle the 1/4 cup of chocolate chips over the sauce.

Step 8

Using the remaining cookie dough, spread evenly across the top (it doesn't need to completely cover the peanut butter caramel layer).

Step 9

Sprinkle lightly with kosher salt.

Step 10

Bake for 18-20 minutes, until the cookie dough on top is slightly browned.

Step 11

Let cool completely before removing from pan and cutting.