Preheat the oven to 350 F and grease donut pans well with butter (preferable- for flavor) or nonstick spray. Lightly dust pans with flour. Tap out excess flour.

In a large bowl, sift together the flour, baking powder, nutmeg, cinnamon, sugars and salt.

In a medium bowl whisk together the buttermilk, egg, vanilla, and melted butter. Pour the wet ingredients into the dry ingredients and stir until just combined. Stir in the sprinkles. Be careful not to overmix. Overmixing may cause the sprinkles to bleed. 

Use a piping bag or zip lock bag with a corner snipped off or spoon to fill the dough into the molds evenly. For average sized baked donuts, fill molds half full. For larger donuts, fill them between 2/3 and 3/4 full.

Bake 10-12 minutes until toothpick comes out dry or edges are lightly browned. Check for doneness with a toothpick. Let cool in the pans for 2-3 minutes then remove from pan and let donuts cool completely on wire rack.

Chop chocolate using a serrated knife. Place the chopped chocolate in a heatproof bowl. In a small saucepan on low heat, heat the heavy cream til just before it starts to boil. Pour over the chopped chocolate. Do not stir.

Allow to sit for 3 minutes then stir till smooth.

Dunk cooled donuts into the ganache. Set donuts on a baking rack. Sprinkle with additional Christmas sprinkles, if desired. Allow ganache to set. Enjoy!