Gluten Free Doughnuts

Name: Gluten Free Doughnuts
Ingredients: 1 1/4 cups Bob's Red Mill 1 to 1 gluten free flour; 1/4 cup flaxseed meal; 1/4 teaspoon baking soda; 1/4 teaspoon cream of tartar; 1 1/2 teaspoons baking powder; 1/4 teaspoon salt; 2/3 cup sugar; 8 tablespoons unsalted butter, melted and cooled; 1 teaspoon vanilla; 2 eggs whites separated; 1 cup milk (I used coconut); 2 cups powdered sugar; 2-5 tablespoons milk (I used coconut)