A healthier donut recipe that most that are out there.
Whisk flour, starches, baking powder, 1 tsp. cinnamon, ¼ tsp. nutmeg, salt, xanthan, and soda in a bowl; set aside.
Beat butter and ⅓ cup sugar in the bowl of a stand mixer fitted with a paddle attachment until fluffy, 1 minute.Add egg and ½ tsp. vanilla; beat until smooth. Alternate adding flour mixture with buttermilk, beginning and ending with dry ingredients.
Mix until a soft dough forms; let rest 10 minutes.
Heat 2" oil in a 6-qt. saucepan until a deep-fry thermometer reads 350°.
On a lightly floured surface, pat dough into a 9" round about ½" thick. Using a floured 3" donut cutter, cut out donuts; gather and reuse scraps. Working in batches, fry, flipping once, until puffed and golden, 3-4 minutes.
Using a slotted spoon, transfer to a baking sheet with a wire rack; let cool completely.
Toss with remaining sugar; set aside. Whisk remaining cinnamon, nutmeg and vanilla, plus confectioners sugar, molasses, and 2 tbsp. hot water in a bowl until smooth. Dip tops of donuts in glaze and sprinkle with cinnamon; return to rack until glaze is set.