Ingredients

• 6 tablespoon unsalted butter
• 1 cup brown sugar, packed
• 1 egg
• 1 teaspoon vanilla extract
• 1 cup all-purpose flour
• 0.5 teaspoon baking soda
• 0.5 teaspoon sea salt
• 0.67 cup dulce de leche
• 0.25 cup heavy cream
• 2 ounce dark chocolate, chopped
• 1 tablespoon coconut oil
• 1 teaspoon fleur de sel

Steps

1. Preheat oven to 350°F (175°C). Line a 9x9 inch square baking pan with parchment paper, leaving an overhang on two sides for easy removal.
2. Place 6 tablespoons of unsalted butter in a medium saucepan over medium heat. Melt the butter completely, stirring occasionally, about 2 to 3 minutes.
3. Continue cooking the melted butter, swirling the pan frequently but not stirring, until it turns golden brown and develops a nutty aroma, about 4 to 5 minutes. Watch carefully to avoid burning. Remove from heat and let cool for 2 minutes.
4. Transfer the cooled brown butter to a medium mixing bowl. Stir in 1 cup of packed brown sugar until well combined.
5. Add 1 large egg and 1 teaspoon of vanilla extract to the brown sugar mixture. Whisk until fully incorporated and smooth.
6. In a separate small bowl, whisk together 1 cup of all-purpose flour, 1/2 teaspoon of baking soda, and 1/2 teaspoon of sea salt.
7. Add the dry ingredients to the wet ingredients and fold gently with a wooden spoon until just combined. Do not overmix.
8. Pour the batter into the prepared baking pan and spread evenly with a spatula.
9. Bake for 18 to 20 minutes, until the top is light golden brown and a toothpick inserted in the center comes out with a few moist crumbs. The bars should not be fully cooked through at this point.
10. Remove the pan from the oven and let cool for 5 minutes while you prepare the caramel topping.
11. In a small saucepan, combine 2/3 cup of dulce de leche and 1/4 cup of heavy cream over low heat. Stir gently until smooth and fully combined, about 1 to 2 minutes. Do not boil.
12. Spread or pour the warm caramel mixture evenly over the partially cooled blondie bars, smoothing gently with a spatula.
13. Return the pan to the oven and bake for an additional 8 minutes until the caramel is set but still slightly soft.
14. Remove the pan from the oven and allow to cool for 15 minutes at room temperature.
15. Place 2 ounces of chopped dark chocolate and 1 tablespoon of coconut oil in a small microwave-safe bowl. Microwave in 30-second intervals, stirring between each, until completely melted and smooth.
16. Transfer the melted chocolate to a small piping bag or squeeze bottle. Drizzle thin lines of chocolate across the caramel layer in a decorative pattern.
17. Sprinkle 1 teaspoon of fleur de sel evenly over the chocolate drizzle while still wet.
18. Place the pan in the refrigerator for 20 minutes to allow the chocolate and caramel to fully set.
19. Lift the parchment paper overhang to remove the entire batch from the pan. Place on a cutting board and cut into 16 equal squares using a sharp knife, wiping the blade between cuts for clean edges.
20. Serve immediately at room temperature or store in an airtight container at room temperature for up to 5 days.