Mix together all the spices for the chai spice mixture. Preheat oven to 350°F and line two large baking sheets with parchment paper.
Cut the butter into tablespoons, add to a medium saucepan, and heat over medium for 5-7 minutes until the butter turns dark amber. Remove from heat just before it looks too dark; residual heat will brown it further.
Pour the brown butter into the bowl of a stand mixer fitted with the paddle attachment and let cool for 10 minutes.
While the butter cools, whisk together the flour, 1 1/2 tablespoons of the chai spice mixture, baking soda, and salt in a large bowl.
Add both sugars to the brown butter. Beat on medium-high for 1 minute. Scrape down the bowl, then beat in the eggs one at a time on medium-high (about 1 minute each), followed by the vanilla extract until combined.
With the mixer on low, slowly add the flour mixture and mix until no streaks remain.
Whisk together the ingredients for the chai spice sugar coating. Scoop 2 tablespoons of dough, roll into balls, then roll in the chai spice sugar. Place 6-8 scoops on each baking sheet spaced a few inches apart.
Bake for 12-14 minutes at 350°F, until the edges are set and the middles are still soft.
Let cool on the baking sheet for 15 minutes to set before serving.