In a large bowl, whisk together dry ingredients: flour, baking powder, baking soda, and salt. Set aside.
Add softened butter and sugars to a large mixing bowl and use an electric mixer to beat together on medium speed until combined and creamy, about 2 minutes. Add eggs one at a time, mixing after each addition until just combined. With the last egg, add in vanilla extract.
On low speed, gradually add the dry ingredients to the butter/sugar mixture. Mix until fully combined, but don't over-mix.
For best results, cover the dough and chill for 2 hours, or up to 3 days. (see notes)
Take the dough out of the refrigerator and allow it to slightly soften at room temperature for 10 minutes, if you had it chilling for more than 2 hours.
Preheat oven to 365ºF or 185ºC. Line 2 large baking sheets with parchment paper or silicone baking mats.
Scoop about 2 tablespoons (40 grams) of dough, roll into a ball and place 3-inches apart onto the lined cookie sheet.
Bake for 10-12 mins. Remove from the oven right when edges start getting golden. They will still appear soft in the middle but will continue to cook in the center on the baking sheet after being removed from the oven.
If desired, while the cookies are still warm, sprinkle with coarse sea salt. Cool for 5 minutes on the baking sheet. Transfer cookies to a cooling rack to cool completely. Cookies stay fresh covered at room temperature for up to 1 week.