Heat the cider in a small saucepan and bring to a simmer. Reduce heat and simmer until the cider has reduced to 1/2 cup. Set aside to cool.
Preheat the oven to 400 degrees and spray a 2 mini-doughnut pans (or 2 regular doughnut pan) with gluten-free cooking spray. (Tip: if you need to bake the doughnuts in more than one batch, make sure to re-spray the pan with gluten-free cooking spray)
Beat the butter and sugar together in a large bowl. Beat in the eggs, buttermilk, vanilla and reduced cider until combined. Add the flour blend, almond flour, xanthan gum, baking powder, baking soda, cinnamon, salt, nutmeg and cloves and beat until smooth.
Pour the mixture into a large zip-top bag and snip about 1/2 inch off one corner. Carefully pipe mixture into your prepared doughnut pan, filling each well about 1/2 full. Do NOT overfill the doughnut wells or your doughnuts will come out looking more like leprechaun hats.
Bake the doughnuts until they spring back when gently touched, about 8 minutes for the minis, 10 minutes for the larger ones.
Dip or brush the doughnuts with the melted butter just as soon as they are cool enough to handle and gently toss with the cinnamon/sugar mixture.