Gather all your ingredients and measure them out.
Pour 1 cup of apple cider into a measuring cup and set aside.
In a large mixing bowl, whisk together the dry ingredients: gluten-free flour, baking powder, baking soda, cinnamon, nutmeg, and salt.
In another bowl, mix the wet ingredients: apple cider, granulated sugar, brown sugar, eggs, melted butter, and vanilla extract until smooth.
Gradually add the wet mixture to the dry ingredients, stirring gently until just combined.
Fill each cavity of your greased donut pan about 3/4 full with the batter.
Bake in a preheated oven for 12-15 minutes until lightly golden and a toothpick comes out clean.
Allow the donuts to cool in the pan for 5 minutes, then transfer to a wire rack.
Mix granulated sugar and cinnamon for coating, then roll each cooled donut in the mixture until fully coated.