Dulce de Leche Blondies
Finally, the chewiest, gooiest, most butterscotch-y bar cookie of your dreams. This is your lifetime Blondie. Period.
Equipment
- Kitchen Scale (optional but HIGHLY RECOMMENDED FOR ALL YOUR BAKING)
- Stand Mixer or Hand Mixer
- 9-inch x 13-inch x 2-inch aluminum baking pan OR (2) 8-inch x 8-inch x 2-inch pans
- Parchment paper
- Stock pot, at least 5 qt. (only needed if making Dulce de Leche)
- Stick Blender, Regular Blender, or Food Processor (optional for making Dulce de Leche)
Ingredients
Blondies
- 2 ½ cups all-purpose flour (11.5 oz)
- 2 sticks unsalted butter (8 oz)
- 1 ¼ cups white chocolate or caramelized white chocolate (7 oz)
- 2 cups light or dark brown sugar, packed (16 oz)
- 1/2 cup granulated sugar (3.5 oz)
- 1/2 cup malted milk powder (2 oz)
- 1 ¼ tsp kosher salt
- 6 eggs, large and straight from fridge
- 1 tbsp pure vanilla extract
Dulce de Leche
- 1 gallon whole milk
- 4 cups granulated sugar
- 1 ½ tsp baking soda
- 2 tsp kosher salt
- 1 tbsp pure vanilla extract
Instructions
Blondies
- Caramelize the white chocolate (optional): Preheat oven to 250°F. Weigh out 12 oz of white chocolate and chop into pieces approximately the size of a quarter. (In order for the caramelization to work, you must use high quality white chocolate such as Valrhona Ivoire. White chocolate baking chips of any kind will NOT work.)
- Evenly layer the chopped white chocolate in either a glass baking dish or on an aluminum baking sheet with parchment paper. Bake the chocolate in 10 minute intervals. At each interval, remove the chocolate from the oven, stir it and re-spread it evenly, then return it to the oven. After 60-70 minutes, the chocolate will be the color of peanut butter and smell buttery and toasty. Weigh out 7 oz of the caramelized chocolate into a medium bowl and set aside. The remaining chocolate can be kept in the fridge for at least a month.
- Prepare the pan(s): Preheat the oven to 350°F and move the rack into the middle. Lightly spray the pan(s) with nonstick spray. Line the pan with parchment paper so that the paper comes up at least 3 inches above the lip of the pan on all 4 sides. You will use the paper edges to lift the blondies from the pan, once they are cooled.
- Brown the butter: In a small saucepan, melt butter over medium heat. The butter will sputter and foam. Keep a close eye on it. As it begins to brown, carefully stir it with a wooden spoon to scrape all the brown bits from the bottom of the pan. When the butter is a golden brown, remove it from heat. It will continue to cook and become a darker brown. Scrape the pan a few more times to make sure the brown bits don't stick to the bottom. Let the butter cool for 5 minutes, then pour it over the (caramelized) white chocolate and gently whisk to combine.
- Mix the Blondie batter: Combine both sugars, the milk powder, salt, eggs (straight out of the fridge!), and vanilla in the bowl of your stand mixer. Use the whisk attachment to whip the mixture on medium-high speed for a full 8 minutes. The mixture will increase in volume and become light and fluffy. Stop the mixer, drizzle in the butter and chocolate mixture, and whip on low to combine. Fold in the flour by hand to avoid over mixing. Make sure there are no streaks of flour remaining.
- Pour the batter into the prepared pan(s). If using the dulce de leche, weigh out 16 oz and warm it in the microwave for 30 seconds. Drizzle it evenly over the entire surface of batter. Pull a butter knife or offset spatula through the batter to marble the dulce de leche. Bake until the blondies are just barely firm in the middle - 35-45 minutes, depending on the pans used and your oven. Cool for 1 hour and then use paper "handles" to remove from pan. Allow to cool completely before cutting into squares. Drizzle with more of the dulce de leche and sprinkle with Maldon sea salt, if desired.
Dulce de Leche
- Pour the entire gallon of milk into the stock pot, add the sugar, and stir to combine. Set the mixture over high heat and keep an eye on it so you can catch it before it boils over. This should take 20-30 minutes. Meanwhile, mix the baking soda with 2 tbsp warm water and set aside.
- Once the milk comes to a boil, remove it from heat. Slowly add the baking soda mixture, just 1/2 tsp at a time, waiting 30 seconds between each addition, so that it won't boil over. Give it a very gentle stir (again, to avoid causing the milk to boil over) and immediately return to medium heat.
- Allow the milk to simmer, uncovered, without stirring for at least 3 hours. You can certainly cook the dulce de leche at a boil in less than 2 hours. Cooking it at a lower temperature, however, will give you a deeper, more complex flavor.
- Once you hit the 3 hour mark, stay close to the pot. The dulce de leche should be a deep brown color and have reduced by over half. Watch for it to start boiling slowly, like molten lava. This is the point where you have to start stirring. Use a wooden spoon to stir continuously, for 10-20 minutes, constantly scraping the bottom of the pan, to allow the dulce de leche to continue to thicken without burning.
- The dulce de leche will be properly thick when: 1. As you quickly scrape the pot, you can see the shiny metal bottom for a flash of a second. 2. It coats the back of the spoon without running off. 3. It is a very dark brown, almost the color of melted dark chocolate.
- Turn off heat and allow the dulce de leche to cool for 10 minutes before pouring it through a strainer into a medium bowl. You should have between 5 and 6 cups. Stir in the vanilla and salt and adjust to taste. For an extra smooth product, run a stick blender through it for 30 seconds. If you don't have a stick blender, a regular blender or a food processor will work just fine. Pour the dulce de leche into heat-proof containers and allow to cool on counter completely before refrigerating. Dulce de leche will keep well for several months in the fridge but there's not much chance it will be around for long!