Step 1

PreparationMake the cookies: Cook butter and cardamom in a small saucepan over medium heat, stirring occasionally, until butter is golden brown and fragrant, 6–8 minutes. Let stand 15 minutes, then strain butter through a fine-mesh sieve into a small bowl. Freeze until just firm, about 15 minutes.

Step 2

Meanwhile, whisk flour, salt, and baking powder in a small bowl.

Step 3

Transfer butter to the bowl of a stand mixer fitted with the paddle attachment; add sugar. Beat on medium-high speed until pale and well combined, about 2 minutes. Add egg and beat until combined, scraping down sides of bowl as needed. Add dry ingredients and pistachios and beat on low speed just until combined.

Step 4

Turn out dough onto a clean work surface. Divide in half. Place each half on a 9x13" sheet of parchment paper with the long end facing you. Roll dough into 2 logs about 1 1/2" in diameter. Wrap each in parchment paper, making sure to cover ends completely. Chill until firm, at least 1 hour or up to overnight.

Step 5

Position racks in upper and lower thirds of oven; preheat to 350°F. Let dough stand at room temperature until soft enough to slice, about 15 minutes. Slice logs into 1/4"-thick rounds. Arrange rounds on 2 parchment-lined rimmed baking sheets about 1" apart. Bake cookies, rotating sheets halfway through, until bottoms are lightly golden, 12–15 minutes. Transfer sheets to wire racks and let cool.

Step 6

Make the glaze and assemble the cookies: Combine chocolate and oil in a small heatproof bowl. Heat in 10-second intervals in microwave, stirring, until melted and combined, 30–40 seconds total.

Step 7

Dip cookies halfway into melted chocolate and transfer to parchment-lined baking sheets. Sprinkle chocolate with pistachios. Chill until chocolate is set, about 10 minutes.

Step 8

Do ahead Dough can be made up to 2 weeks ahead; keep frozen. Let stand at room temperature until soft enough to slice, about 30 minutes.

Step 9

Cook's NotePurchase bar chocolate for this recipe. White chocolate chips melt poorly.