Begin by creaming together the butter and 1 ¼ cups of sugar with a mixer. When it is fully mixed together, it should look like really light and fluffy butter.
While the butter and sugar mix together, sift the flour, salt, cream of tartar, and baking powder together in a large bowl and place it off to the side.
Next, add eggs to the creamed butter and sugar until fully incorporated, one at a time.
When the eggs are fully mixed in, add apple butter, vanilla extract, and ½ a teaspoon of cinnamon and mix until well combined.
Now, add the sifted flour in small increments - I usually just use a measuring cup and mix it in a little at a time. (If you add all the flour at once and turn on the mixer, the flour will poof up into a cloud and make a huge mess.)
After the flour is fully mixed in, either cover the bowl or transfer the dough to wax paper and place in a zip-top bag.
Move dough to the refrigerator for a minimum of 2 hours. If you are in a hurry to bake cookies, you can put it in the freezer for 30 minutes, but do not bake the dough from frozen - it will take much longer and the cookies won't bake the same. (You also want the dough to be soft enough to roll into balls.)
When you are ready to bake cookies, preheat your oven to 350°F. Then combine ⅓ of a cup of sugar with 1 ¼ teaspoons of cinnamon. (I usually just mix the two together with a fork.)
Now, using a spoon or a scoop, make uniformly sized balls of dough and roll them in the cinnamon sugar. I like to do a double roll and roll them in the sugar mixture two times - the first time gets sugar onto the cookies and the second sits on top and gets crispy when you bake the cookies.
Now, bake the cookies at 350°F for 12 - 14 minutes. I like to let the cookies get slightly browned and a little crispy on the outside - it gives them the texture of a cinnamon sugar donut.
Let cool for a few minutes so you don't burn your mouth, but these cookies are best served while still warm!