Opal Apple Donuts: Apple Cider

Ingredients

• 1 Opal Apple, peeled, cored, and chopped
• 2 cups apple cider
• 4 cups all-purpose flour
• 1 tablespoon baking powder
• 1 teaspoon ground cinnamon
• 1 teaspoon salt
• 1/2 teaspoon baking soda
• 1/2 teaspoon ground nutmeg
• 1 cup sugar
• 4 tablespoons unsalted butter, melted
• 2 eggs, room temp
• 1/2 cup buttermilk, room temp
• 1 teaspoon vanilla extract
• 3 tablespoons cookie butter
• 3-4 tablespoons cup milk
• 1 tablespoon powdered sugar
• 1/2 teaspoon vanilla extract