Preheat the oven to 425˚F. Line a muffin pan with liners and set aside.
Mix together the sugar, melted butter, nutmeg, and cinnamon.
Stir in buttermilk and vanilla until fully incorporated.
Add in cake flour, baking soda, and salt. Mix just until combined.
Let the batter rest at room temperature for 15 minutes.
Portion out the batter into muffin tins, about 3 to 4 tablespoons each. I like to use a medium cookie scoop for this using two scoops per muffin.
Bake for 7 minutes then reduce the temperature to 375˚F and bake for an additional 12 to 15 minutes until a cake tester or toothpick comes clean from the center of the muffins.
Let the muffins cool in the pan for 20 to 30 minutes before removing and topping.
Prepare the glaze by mixing together the powdered sugar, vanilla, and half and half until smooth, then dip the muffins in it and let them sit until the glaze has hardened about 30 minutes.
Or brush the tops of the muffins with melted butter and dip them in cinnamon sugar and enjoy right away.