Start by preheating your oven to 350°F (175°C). This ensures the oven is at the right temperature when you’re ready to bake.

Next, line an 8x8-inch baking pan with parchment paper or foil. Leave an overhang on two sides—this makes it super easy to lift the blondies out of the pan later. Lightly grease the parchment or foil with a little butter or nonstick spray to prevent sticking.

In a large mixing bowl, combine 1 cup (230g) of melted unsalted butter and 1 ½ cups (300g) of packed light brown sugar. Use a whisk or a spatula to mix them together until the mixture is smooth and glossy.

Add 2 large eggs (make sure they’re at room temperature!) and 1 teaspoon of vanilla extract. Whisk everything together until the eggs are fully incorporated and the mixture looks creamy.

In a separate bowl, whisk together 2 cups (250g) of all-purpose flour, 1 teaspoon of baking powder, and ½ teaspoon of salt. This ensures the leavening agents and salt are evenly distributed.

Gradually add the dry ingredients to the wet ingredients. Use a spatula to fold everything together until just combined. Be careful not to overmix—this can make the blondies tough. The batter should be thick and smooth.

Now comes the fun part! Add 1 cup (150g) of white chocolate chunks or chips and ½ cup (60g) of chopped pistachios to the batter. Fold them in gently until they’re evenly distributed. If you’d like, save a small handful of white chocolate and pistachios to sprinkle on top before baking for extra texture and visual appeal.

Pour the batter into the prepared baking pan and spread it out evenly with a spatula. Make sure the batter reaches all the corners and is smooth on top.

Bake in the preheated oven for 25-30 minutes. Keep an eye on them—the blondies are done when the edges are golden brown and the center is set but still slightly soft. A toothpick inserted into the center should come out with a few moist crumbs but not wet batter.

Once baked, remove the pan from the oven and let the blondies cool completely in the pan. This is important—it allows them to set and makes them easier to slice.

When the blondies are completely cool, use the parchment paper overhang to lift them out of the pan. Place them on a cutting board and slice into 16 squares using a sharp knife or a bench scraper.

For an extra touch of elegance, melt 2 tablespoons of white chocolate and drizzle it over the cooled blondies. Sprinkle with a few extra chopped pistachios for a pop of color and crunch.