Mix wet ingredients: Melt the butter in the microwave or in a small saucepan over medium-low heat. Transfer it to a large mixing bowl and let it cool completely (about 20 minutes). Stir in the maple syrup, followed by the brown sugar, and mix until smooth. Mix in vanilla extract and egg and stir until well combined.

Combine dry ingredients: In a medium bowl, whisk together the flour, cornstarch, baking powder, baking soda, salt, and all but 2 teaspoons of the chai spice blend. (We will reserve some of the chai spice. blend for the rolling sugar mix). Gradually stir the dry ingredients into the wet mixture until no streaks remain.

Chill: Cover and refrigerate dough for at least 2 hours (or up to 5 days).

Make the rolling sugar: Stir the reserved chai spice blend into the granulated sugar until evenly mixed.

Prep for baking: About 30 minutes before baking, preheat oven to 375°F (190°C) and line a baking sheet with parchment. Scoop dough into 2-tablespoon (about 40g) portions. I find it's easiest to do this with a cookie scoop, but you can also just use a spoon. Roll each ball in the chai-spiced sugar mixture until completely coated.

Bake: Arrange on the prepared baking sheet and bake for 10–12 minutes, until the edges are set and centers are still soft. Transfer the baking sheet to a wire rack and let the cookies cool for at least 5 minutes. Serve warm and enjoy!