Saffron Pistachio Blondies

Saffron and pistachio, a combination known to many on the Indian subcontinent as kesar pista, is a classic flavoring in South Asian, Iranian and other desserts — and for good reason. The buttery richness of pistachios brings out the floral flavor in saffron. Kesar pista shines in other sweets like this nutty twist on a blondie. Seth Byrum, my partner and an avid home baker, suggested enriching the base with white chocolate, which feels reminiscent of khoya, the richly flavored milk solids in several South Asian confections. The radiantly golden frosting lets the saffron do the talking. Garnish the top with pistachios to mimic the top of more traditional South Asian sweets, like shrikhand.

Ingredients

• ¾

  cup/112 grams raw, unsalted pistachios, plus more for garnish

• 1

  cup/130 grams all-purpose flour

• ¾

  teaspoon coarse kosher salt 

• ¾

  teaspoon baking powder 

• ½

  teaspoon ground cardamom

• ¾

  cup/173 grams unsalted butter, melted and cooled 

• 1 ¼

  packed cups/250 grams dark brown sugar

• 2

  large eggs, at room temperature 

• ½

  cup/87 grams white chocolate chips

Preparation

1. Make the bars: Heat oven to 350 degrees. Line a 9-inch square baking pan with parchment paper such that the paper spills out over the sides of the pan, like wings.
2. In a food processor, pulse the pistachios until the nuts are very finely ground. Don’t let them get pasty. Add the flour, salt, baking powder and cardamom and pulse to combine.
3. In a large mixing bowl, whisk together melted butter and brown sugar until smooth and shiny. (The butter will separate at first, then blend in.) Whisk in the eggs until incorporated. Add the pistachio mixture and mix with a silicone spatula to combine. Gently stir in the white chocolate chips until evenly distributed. Pour the batter into the prepared pan and spread in an even layer. 
4. Bake until the sides are brown and pull away from the pan, and the middle is slightly paler in color, 25 to 27 minutes. A toothpick inserted in the center will come out with a few crumbs attached. Cool completely in the pan on a rack.
5. While the bars cool, make the frosting: Finely grind the saffron threads in a mortar using a pestle or in a microwave-safe bowl using the back of a spoon. If needed, transfer the ground saffron to a microwave-safe bowl or to a small saucepan if you don’t have a microwave. Stir in the milk, and microwave on high or heat over medium until the mixture is frothing around the edges but not boiling, about 30 seconds. Place the bowl in the refrigerator or freezer to quickly cool the mixture. 
6. Meanwhile, in a large bowl, use an electric hand or stand mixer or a heavy whisk or wooden spoon to beat the cream cheese and butter until smooth. If working by hand, this takes some muscle. Add the confectioners’ sugar and salt and beat again until homogeneous and no clumps of sugar remain. Beat in the cooled saffron milk until well-combined. The frosting will turn a bright golden hue.
7. Once the bars have cooled completely, scrape the frosting over the top, and use a spatula to spread it evenly. Crush or chop some pistachios for garnish and sprinkle all over the top. Refrigerate for at least 2 hours before eating. The bars keep in an airtight container in the refrigerator for up to 5 days or in the freezer for 1 month.