01 - Preheat oven to 350°F and lightly grease a 12-cavity donut pan with cooking spray or butter.
02 - In a large bowl, whisk together sweet rice flour, tapioca starch, baking powder, salt, sugar, cinnamon, and nutmeg until evenly blended.
03 - In a separate bowl, whisk eggs, milk, pumpkin puree, melted butter, and vanilla extract until completely smooth.
04 - Pour wet ingredients into dry ingredients and stir gently until just combined; avoid overmixing to prevent tough texture.
05 - Transfer batter to a piping bag or zip-top bag with corner snipped off. Pipe evenly into donut cavities, filling each about 3/4 full.
06 - Bake for 20-25 minutes until donuts are puffed and lightly golden. Cool in pan for 5 minutes, then release onto wire rack.
07 - Whisk powdered sugar, maple syrup, and salt together. Add milk 1 teaspoon at a time until thick but pourable consistency forms.
08 - Dip tops of completely cooled donuts into glaze, letting excess drip off. Return to wire rack and allow glaze to set before serving.