Frosted Sugar Cookies ? Recipe

Ingredients

• 1/2 cup unsalted butter, softened to room temperature
• 3/4 cups sugar
• 1 large egg, room temperature
• 1/2 cup sour cream, room temperature
• 1 teaspoon pure vanilla extract
• 1 1/2 cups all purpose flour
• 1 tablespoon cornstarch
• 1/2 teaspoon baking powder
• 1/4 teaspoon baking soda
• 1/4 teaspoon salt
• Frosting: 1/2 cup unsalted butter , room temperature
• 2 1/2 cups powdered sugar
• pinch salt
• 3-4 tablespoons heavy cream
• food coloring to color frosting
• candy sprinkles to decorate