Chef John's Orange-Pistachio Greenies Recipe

Whisk 2 tablespoons orange zest into melted butter in a mixing bowl followed by white sugar until sugar has dissolved about 2 minutes. Whisk in eggs until light and fluffy about 2 more minutes. Stir 1 tablespoon orange juice milk and vanilla extract into egg mixture.

Place pistachios into a food processor and pulse until coarsely ground. Add salt baking powder and flour to pistachios; pulse until combined 3 to 4 times. Stir pistachio mixture into wet ingredients until batter is combined. Gently fold in chocolate chips.

Preheat oven to 350 degrees F; generously butter a 9x9-inch square baking dish.

Spread batter into prepared baking dish. Tap the dish several times on a sturdy work surface to eliminate air bubbles.

Bake in the preheated oven until top is lightly golden brown and a toothpick inserted into the center comes out clean 20 to 25 minutes.

Stir 1 tablespoon orange juice with 2 teaspoons orange zest in a small bowl; mix in confectioners' sugar to form a thin runny glaze. Drizzle glaze on top of pistachio bars and spread to cover top. Cut into squares once cooled.