Preheat the oven to 350°F/ 177°C. Spray a standard 12-cup or 2 6-cup donut pans with non-stick spray. Set aside.
In a large bowl, whisk together the pumpkin puree, both sugars, the baking powder, the salt and all the spices. Then whisk in the eggs, oil, milk & vanilla until combined.
Add the flour and then gently fold everything together until just combined and no flour streaks remain.
Pour the batter in a large piping bag or zip-top bag. Seal and snip a corner off the bottom of the bag and pipe the batter into each greased donut space, filling about three-quarters of the way.
Bake for about 14-16 minutes or until the edges are lightly browned and they spring back when gently touched at the tops. Cool the donuts in the pan for 5 minutes then transfer to a wire rack. Cool the donuts completely before icing them.
Combine the brown sugar, milk and butter in a medium saucepan over low heat. Stir until the butter is melted and everything is smooth, then bring to a simmer. Simmer for 1 minute then whisk in the maple syrup, simmer about 30 seconds more, then remove from the heat. Stir in the vanilla, sifted confectioners’ sugar and salt until smooth and combined. Let the icing cool a few minutes to thicken.
Dip the tops of the pumpkin donuts into the warm glaze. If the glaze starts getting too thick as you’re dipping, you can hold back over the stove for a few seconds to reheat as necessary. Lay the glazed donuts on a wire rack to set. *Sprinkle on any toppings like sprinkles or nuts before the glaze hardens.
Enjoy once the glaze sets or store in an airtight container at room temperature for up to 2 days or in the refrigerator a week.