Preheat your oven to 350°F (175°C). Prepare your 9X13 brownie recipe according to the instructions, either homemade or gluten-free box mix. Pour the batter into a greased pan and bake for 25–30 minutes, or until a toothpick comes out with a few moist crumbs. Cool completely in the pan.

In a microwave-safe bowl, combine the unwrapped caramels and 2 tablespoons of milk. Microwave on high for 30 seconds, then stir. Repeat heating in 15-second intervals, stirring until almost fully melted. Stir in 1 ½ cups of chopped pecans and pour over the cooled brownies.

In a medium bowl, mix 6 tablespoons of softened butter and ¾ cup of creamy peanut butter until smooth. Gradually incorporate 1 ½ cups of powdered sugar and 2 tablespoons of milk until creamy. Spread over the caramel layer.

Combine 1 cup of semi-sweet chocolate chips with 1 ½ teaspoons of oil. Microwave in 30-second intervals, stirring until smooth. Pour over the peanut butter layer and spread evenly. Optionally sprinkle with fleur de sel.

Chill in the refrigerator for about 30 minutes or until set. Cut into squares and serve at room temperature.