Blondies:

Step 1: In a saucepan melt the butter and let it cool slightly.

Step 2: In a mixing bowl, stir the melted butter with white and brown sugar. Add the eggs and lemon extract and beat on high speed for 2–3 minutes until the mixture turns pale yellow and frothy.

Step 3: In a separate bowl, mix the flour, baking powder, and salt. Gradually add the dry mixture to the wet mixture, stirring until just combined.

Step 4: Melt the white chocolate over a water bath (double boiler) and slowly fold it into the batter.

Step 5: Roughly chop the pistachios and fold them into the batter.

Step 6: Line a 24 x 24 cm baking pan with parchment paper and pour the batter into the prepared pan. Smooth the top.

Step 7: Preheat the oven to 175°C (350°F). Bake the blondies for 50–55 minutes. After about 25 minutes, loosely cover the pan with aluminum foil to prevent over-browning.

Step 8: After 50 minutes, insert a toothpick into the center. If it comes out with wet batter, bake for another 5 minutes. Let the blondies cool completely.

Cream Cheese Frosting:

Step 1: In a mixing bowl, beat the cream cheese, softened butter, and lemon extract until smooth and creamy.

Step 2: Gradually add the Icing sugar and beat until the frosting is fluffy and well combined.

Assemble:

Step 1: Spread the frosting evenly over the cooled blondies.

Step 2: Garnish with chopped pistachios.