Preheat oven to 350°F. Line a 9x9-inch baking pan with parchment paper. Set aside.
Using a hand mixer, cream the butter, sugar, flour, salt, and vanilla together until crumbled and fully incorporated.
⅔ cup unsalted butter, ¼ cup granulated sugar, 1¼ cups all-purpose flour, ¼ teaspoon kosher salt, 1 teaspoon pure vanilla extract
Press the shortbread mixture into the bottom of the lined baking dish and bake for approximately 20 minutes, until slightly golden.
Remove from the oven and set aside to cool slightly.
Place the caramels and the cream in a microwave-safe bowl and microwave for 2 minutes, stopping and stirring every 30 seconds. Stir in the peanuts and pour the mixture evenly over the shortbread. Use a spoon to distribute the caramel evenly.
11 ounces baking caramels, ¼ cup heavy cream, 1 cup dry roasted unsalted peanuts
Allow to cool for at least 10 minutes.
In a microwave-safe bowl, heat the chocolate chips in increments of 30 seconds, stirring each time, until melted.
12 ounces milk chocolate chips
Pour the chocolate over the caramel and spread evenly.
Allow the chocolate to cool and harden completely before serving, about 2 hours. You can speed up the process by letting it cool in the refriggerator. Cut into squares and serve!