Brown the butter and pour into stand mixer. Lightly beat with paddle to help cool it down. It should get very cool before continuing.

Soft together flour, cream of tartar, baking soda, cinnamon, nutmeg, and salt.

Whisk eggs and milk.

Add granulated sugar and brown sugar to butter, it should cream a bit.

Turn mixer on low and stream in the egg mixture, then medium speed to combine.

Add flour mixture in 3 parts

Refrigerate at least 1 hour but up to 24 hours.

Preheat oven to 400°F.

Stir together cinnamon and granulated sugar in bowl. Use small cookie scoop and roll in mixture.

Bake 9 to 12 minutes.