Preheat oven to 350°F (177°C). Spray the donut pan with non-stick spray and set aside.

Whisk the flour, baking powder, baking soda, salt, cinnamon, and nutmeg together in a medium bowl and set aside.

Whisk the egg, brown sugar, and buttermilk together until smooth. Add the melted butter and vanilla, whisking until fully combined.

Pour the wet ingredients into the dry ingredients and mix until just combined. Do not overmix. The batter will be very thick.

Spoon the batter into the donut cavities, filling only 1/2 to 2/3 full. Do not fill too much to maintain the hole in the center.

Bake for 8-10 minutes or until the edges are lightly browned. Allow to cool in the pan for about two minutes, then transfer each donut to a wire rack.

In a medium bowl, whisk the glaze ingredients together until completely smooth. Adjust consistency with more cream or confectioners’ sugar as desired.

Dip each donut into the glaze, then place back on the rack and top with sprinkles. Donuts are best served immediately.