In a mixing bowl combine the flour, granulated sugar, baking powder, salt, cinnamon and nutmeg. Stir together and set aside.

In a large mixing bowl combine the eggs, buttermilk, vegetable oil, and vanilla extract. Stir to combine.

Gradually mix the dry ingredients into the wet ingredients, mixing just until combined. The batter will be very thick.

Cover the bowl with a towel and allow the batter to rest for 15 minutes. During this time, preheat the oven to 425ºF / 220ºC.

For bakery style muffins, line a 12 count muffin pan with 6 muffin liners, meaning you’ll only fill every other muffin well with batter. Fill the liners with 2 tablespoons of batter.

Heat the nutella in the microwave until melty. Drop 1 teaspoon of nutella into each muffin cup, spread into an even layer. Add 2 tablespoons of batter, covering the first layer of nutella. Then drop 1 more teaspoon of nutella, spread into an even layer. Fill the muffin cups with about 4 tablespoons of batter.

Top each muffin with a little bit of nutella, swirling it into the batter with a toothpick. Sprinkle the tops with sanding sugar.

Place one pan in the center of the oven and bake for 7 minutes at 425ºF / 220ºC, then keep the muffins in the oven, turn the temperature down to 350ºF / 180ºC and bake for 16-20 minutes or until a toothpick inserted in the center comes out clean. Allow the muffins to cool in the pan. Repeat with the remaining batter, bumping the temperature back up to 425ºF / 220ºC.