Cream together softened butter and 1 1/2 cups of sugar. Add eggs and mix until smooth.
Add flour, baking soda, salt, and cream of tartar, and stir until combined.
Refrigerate at least 30 minutes. While dough is chilling, combine 1/4 cup of sugar and cinnamon in a small bowl (add more cinnamon if desired.) Set aside until it’s time to bake the cookies.
Preheat oven to 350 degrees.
Remove dough from refrigerator. Scoop out tablespoon size chunks of dough. Roll in your palms to form a smooth ball. Roll in cinnamon sugar mixture. Place on an ungreased cookie sheet. Repeat. Make sure to place balls 2 inches apart on cookie sheet.
Bake for 10 minutes or until slightly browned around the edges. Remove from oven and let the cookies sit in the pan for one minute. Transfer cookies to cooling racks until cooled.