Cream butter for 1 minute, then add sugar; cream for at least 2 more more minutes, until light in color and fluffy. Scrape down sides during mixing as needed.
Add egg and vanilla, and mix for 30 seconds to combine, scraping down sides.
In a bowl, combine gluten-free flour, baking powder, baking soda, cream of tartar, salt. Whisk to combine.
Add dry mixture in two increments to the wet ingredients, with stand mixer on speed 2, low. Turn up to speed 3 for 30 to 45 seconds to fully combine, so no flour streaks are left. Stir in white chocolate. Refrigerate dough for 1 hour (or overnight) to allow dough to rest and absorb liquids.
When ready to bake, preheat oven to 375 degrees F. Scoop dough into dough balls about 2 tablespoons big; they should be 60 grams each. Roll in cinnamon. Place 5 dough balls on a parchment lined baking sheet with lots of room in between.
Bake for 9 minutes, then use pan-banging technique; lift one corner of the cookie sheet and let drop onto rack. Then do the same thing to one other corner. Let cookies bake for another 1 1/2 to 2 minutes (you'll see their centers will puff up), repeat the banging. Let cookies bake for another 1 minute, repeat the banging. They'll bake a total of 12 to 13 minutes; you want them to be set in the middle but slightly underbaked when you pull them out of oven to ensure chewiness. Remove cookies from oven and let cool for 6-7 minutes before transferring to wire rack to finish cooling.