Preheat the oven to 350ºF and line two baking sheets with parchment paper or silicone baking mats. Set aside.
In the bowl of a stand mixer or electric hand mixer, add the coconut oil, brown sugar, and granulated sugar. Turn on low speed. Pour in milk and mix until fluffy, 3-4 minutes.
Add eggs and vanilla mixing on medium until smooth and well incorporated.
With mixer off add in the flour, baking powder, baking soda, and salt. Stir on low just until combined. Do not over mix.
In a separate small bowl, whisk together the granulated and brown sugar to remove any lumps
Using a 2-tablespoon scoop, scoop dough and roll into a ball between your palms then toss in the sugar mixture to coat all sides. Place onto a cookie sheet about 2 inches apart.
Bake until the edges are just brown and tops start to crackle, about 10-12 minutes, rotating trays front to back and top to bottom halfway through baking. Cookies may look underdone and slightly puffed when you remove them from the oven. They will continue to bake on the trays. Allow cookies to cool on the trays