Slice and Bake Halloween Cookies

Name: Slice and Bake Halloween Cookies
Prep time: 2 h
Cook time: 10 min
Total time: 2 h 10 min
Cuisine: American
Ingredients: 18 oz all-purpose flour ((4 1/4 cups) ); ½ tsp salt; 8 oz cold unsalted butter (cubed); 12.25 oz granulated sugar ((1 ¾ cups)); 2 tsp vanilla extract; 2 large eggs; Black gel food coloring ((I used Americolor Super Black)); Purple gel food coloring ((I used Americolor Electric Purple and Regal Purple)); 1 large egg white; Small Halloween cookie cutters; Black sugar sprinkles