Heat oven to 350°F. Line two baking sheets with parchment paper.
Cream softened butter and 0.6 cup powdered sugar in a large bowl until smooth and fluffy.
Mix in vanilla, almond extract if using, and salt until combined.
Stir in flour in two additions just until a soft dough forms. Fold in chopped pistachios.
Chill dough 20 minutes to firm slightly for easier rolling.
Scoop tablespoon portions and roll into 1-inch balls. Arrange 2 inches apart on prepared sheets.
Bake 12–14 minutes, until set and barely golden on the bottoms. Let rest 5 minutes on the sheet.
Roll warm cookies in the coating sugar. Cool completely, then roll a second time for a snowy finish.