Frosted Eggnog Cookies

Name: Frosted Eggnog Cookies
Prep time: 30 min
Cook time: 10 min
Total time: 40 min
Cuisine: American
Ingredients: 1 cup unsalted brown butter (room temperature ); 1 1/2 cups powdered sugar; 1 teaspoon vanilla extract; 1/2 teaspoon rum extract (optional); 1 large egg yolk; 2 tablespoons eggnog; 2 1/4 cups all purpose flour; 1/2 cup almond flour (substitute all purpose flour); 1/2 teaspoon baking powder; 1/2 teaspoon nutmeg; 1/4 teaspoon cinnamon; 1/4 teaspoon kosher salt; 1/2 cup unsalted brown butter (room temperature ); 2 cups powdered sugar; 2-4 tablespoons eggnog (as needed); 1/2 teaspoon rum extract (optional ); wintery sprinkles