For the dough: In a bowl, sift together the flour, baking soda, baking powder, nutmeg and cream of tartar. Set aside. *MAKE SURE YOU GENTLY SPOON YOUR FLOUR INTO YOUR MEASURING CUP, VS SCOOPING THE FLOUR. SCOOPING CAN RESULT IN TOO MUCH FLOUR.
In a separate bowl, cream the butter and sugars until fluffy. Add the eggs, eggnog and vanilla or rum extract. Mix well.
Stir in the dry ingredients. Stir until just combined.
Cover bowl (or remove dough from bowl and wrap in plastic wrap) and chill for 1+ hours.
When ready to bake, Preheat the oven to 350 degrees. Form the dough into 1 inch balls. Mix nutmeg and sugar in a small bowl and roll each ball of dough through the sugar mixture to coat one side.
Place on a greased baking sheet or a cookie sheet covered with wax paper or silicone baking mat.
Bake 8-9 minutes. Do not overbake. Allow to cool on baking sheet for at least ten minutes before transferring to a wire cooling rack.