Sugar Cookies

Sugar Cookie Dough

• 6 oz sugar
• 6 oz unsalted butter, chilled, diced (½ in.)
• 1 large egg
• 1 tsp vanilla extract
• 12 oz all-purpose flour, plus extra to dust
• ¼ tsp baking powder
• ⅛ tsp baking soda
• 1 pinch salt

Royal Icing

• 14 oz sugar, divided
• 1 egg white, from a large pasteurized egg
  ou 3 tbsp liquid egg whites, pasteurized
• 1 tbsp lemon juice
• food coloring (e.g., red, green, silver, blue, gold)
• colored sugar sprinkles
  ou candy canes or peppermint candies, crushed