Pistachio Shortbread

INGREDIENTS

• 1 unsalted, shelled raw pistachios (about 4 1/2 ounces)
• 1 1/4 all-purpose flour
• 3/4 sugar
• 1/2 (1 stick) chilled unsalted butter, cut into 1/2-inch pieces
• 1 kosher salt
• 1/4 vanilla extract