1 cup (2 sticks) unsalted butter, melted and cooled slightly
1 cup light brown sugar, packed
1/2 cup granulated sugar
1 large egg, room temperature
1 tablespoon vanilla extract
1/2 cup pumpkin puree (ensure it is not pumpkin pie filling)
2 cups all-purpose flour
1 teaspoon pumpkin pie spice
1/2 teaspoon baking soda
1/2 teaspoon salt
1/2 cup salted caramel sauce (store-bought or homemade)
Flaky sea salt for sprinkling
Instructions
Preheat your oven to 350°F (175°C). Line an 8×8 inch square baking pan with parchment paper, leaving a slight overhang on the sides to make it easy to lift the blondies out later. Lightly grease the parchment with cooking spray.
In a large mixing bowl, whisk together the melted butter, brown sugar, and granulated sugar until smooth. Add the egg and vanilla extract, whisking until well combined. Stir in the pumpkin puree until the mixture is uniform in color.
In a separate medium bowl, whisk together the flour, pumpkin pie spice, baking soda, and salt. Gradually add the dry ingredients to the wet ingredients, folding them in with a spatula. Be careful not to overmix; stop as soon as no flour streaks remain.
Spread about two-thirds of the blondie batter into the prepared baking pan. Drizzle half of the salted caramel sauce over the batter. Drop the remaining batter in small dollops over the caramel, then drizzle the rest of the caramel on top. Use a knife or a skewer to gently swirl the caramel into the batter.
Place the pan in the center rack of the oven and bake for 28-32 minutes. The edges should be golden brown, and a toothpick inserted into the center should come out with just a few moist crumbs. Do not overbake, or they will lose their fudgy texture.
Remove the pan from the oven and immediately sprinkle a pinch of flaky sea salt over the top. Allow the blondies to cool completely in the pan before lifting them out and slicing into squares. This ensures the caramel sets and the bars hold their shape.