Pumpkin Spice Sugar Cookies

Sugar Cookie Dough

• 4 oz granulated sugar
• 4 oz brown sugar
• 8 oz unsalted butter, chilled, diced (½ in.)
• 1 large egg
• 1 tsp vanilla extract
• 2 ½ oz pumpkin purée
• 12 oz all-purpose flour, plus extra to dust
• 2 tbsp pumpkin pie spice
  o bien 2 tbsp homemade pumpkin spice mix
• ½ tsp salt

Royal Icing

• 14 oz sugar, divided
• 3 tbsp pumpkin purée
• 1 tbsp water
• food coloring (e.g., orange, black)
• colored sugar sprinkles