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Birthday Cake Blondies

These Birthday Cake Blondies are dense, chewy dessert bars with the nostalgic flavor of classic birthday cake batter. Made with melted butter, brown sugar, vanilla, and a touch of almond extract, they bake into soft, buttery blondies with golden edges and a crackly top.
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Prep Time 15 minutes
Cook Time 30 minutes
Cooling Time 3 hours
Total Time 3 hours 45 minutes
Servings: 9 Blondies
Course: Dessert
Ingredients Equipment Method

Ingredients
  

  • 205 g (2 sticks minus 1½ tbsp) unsalted butter melted & slightly cooled
  • 1½ cups light brown sugar packed
  • ½ cup granulated sugar
  • 2 large eggs room temperature
  • 1 tbsp vanilla extract
  • ¾ tsp almond extract
  • 2¾ cup (345g) all-purpose flour
  • 1 tsp cornstarch
  • ½ tsp baking powder
  • ½ tsp salt
  • ½ cup rainbow sprinkles jimmies

Equipment

  • 8x8 or 9x9 baking pan
  • Large mixing bowl
  • Whisk
  • Rubber spatula
  • Measuring cups & spoons
  • Sharp knife for slicing

Method
 

  1. Preheat your oven to 350°F (175°C).
    Grease your baking pan and line it with parchment paper, leaving an overhang on the sides. This makes it easy to lift the blondies out of the pan once they’ve cooled.
  2. In a large bowl, whisk together the melted butter, brown sugar, and granulated sugar until smooth.
    Add the eggs, vanilla extract, and almond extract.
    Whisk the mixture vigorously for two full minutes.
  3. Using a spatula, gently fold in All-purpose flour, cornstarch, baking powder, and salt. Mix only until the flour disappears.
    Fold in two-thirds of the rainbow sprinkles, reserving the rest for topping.
  4. Transfer the thick batter to your prepared pan and spread it evenly with a spatula.
    Sprinkle the remaining rainbow sprinkles over the top.
  5. The material and size of your baking pan can change how blondies bake.
    Metal Pan – 8×8 inch: Bake for 28–32 minutes.
    Metal Pan – 9×9 inch: Bake for 22–26 minutes.
    Ceramic or Glass – 8×8 inch: Bake for 38–45 minutes.
    Ceramic or Glass – 9×9 inch: Bake for 30–35 minutes.
  6. Once the blondies are baked, resist the temptation to cut them immediately. Let them cool in the pan for at least 2 to 3 hours. Once cooled, lift the blondies out using the parchment overhang and cut into 9 bars.