Preheat oven to 350ºF. Line a 9x9 pan with a parchment sling and spray with nonstick baking spray.
In a medium pot on the stove, melt the butter over medium heat. Continue cooking the butter, stirring often, for 5-8 minutes, or until the butter is a medium golden brown color. It will sizzle and foam as it cooks. For a full tutorial, see our post How to Brown Butter. 1 cup butter
Remove from the heat and allow it to cool for about 5 minutes. Add in the vanilla.
1 tablespoon vanilla
In a separate bowl mix together the flour, oats, brown sugar, baking soda, and salt.
1 ½ cup all-purpose flour, 1 ¼ cup old fashioned oats, 1 cup light brown sugar, ½ teaspoon baking soda, ½ teaspoon kosher salt
Pour the butter/vanilla mixture over the dry ingredients and stir with a rubber spatula until evenly combined, but being careful not to overmix.
Scoop ½ of the batter into the bottom of the prepared pan and press it down until evenly distributed. It should go all the way to the edges with no gaps, but it will be a thin layer. Bake for 8-10 minutes.
In a microwave safe bowl or liquid measuring cup, combine the caramel bits and heavy cream. Microwave in 30 second increments, using a whisk to stir very well between each increment, until it is fully melted and smooth. It should take 1.5-2 minutes.
11 ounces caramel bits, ½ cup heavy cream
Remove the pan from the oven. Sprinkle the chocolate over the top of the warm crust going all the way to the edges. Then pour the caramel mixture on top, going all the way to the edges again. Lastly, sprinkle the rest of the cookie dough on top as evenly as possible, reaching all the way to the edges. If the dough is very clumpy, use your fingers to gently break it apart as needed. It’s fine if some small spots of caramel are showing.
1 ½ cups about 8 oz bittersweet chocolate (chips or a chopped baking bar)
Return to the oven and bake for 18-23 minutes more, or until it’s lightly golden brown and cooked through. The caramel will be bubbling on the edges and the center of the batter looks matte instead of shiny.
Allow to cool completely in the pan. Use the parchment sling to lift them out of the pan, then slice them into 16 squares.