Heat oven to 325 degrees F. Spray 8 1/2-by-4 1/2-inch loaf pan with baking spray with flour*; line loaf pan with parchment paper. Spray parchment with baking spray with flour.

In food processor, grind 1/2 cup chopped pistachios to a paste. Add to large bowl or bowl of stand mixer; add butter and cream cheese to bowl. Beat with electric hand mixer or beater blade of stand mixer on medium speed until mixture is smooth.

Gradually beat in sugar. Beat in eggs, one at a time, scraping down sides of bowl after each addition. Beat in vanilla. Add flour and salt; stir until just combined. Fold in remaining 1/2 cup chopped pistachios. Pour and spread batter evenly into prepared pan.

Bake 1 hour 35 minutes to 1 hour 50 minutes until toothpick inserted in center of loaf comes out clean. Cool in pan 20 minutes, then carefully lift loaf from pan using parchment paper and transfer to cooling rack to cool completely.

To make icing: In small bowl, whisk 1/2 cup powdered sugar, heavy cream and lemon juice until smooth. Whisk in just enough remaining powdered sugar until icing is smooth and thick. Spoon evenly over top of cooled loaf (you may not use all of the icing). Sprinkle with chopped pistachios. Let icing set completely before slicing loaf.

*NOTE: Alternatively, you can spray the loaf pan with cooking spray, then dust with flour, tapping out excess.