In a medium to large mixing bowl, cream together the softened butter and sugars. Stir in the egg and vanilla extract until just combined.
In a medium to small mixing bowl, whisk together the flour, salt, and baking powder. Then stir this in with the wet ingredients until a dough ball forms.
Stir in the chocolate chips. Divide into six balls (a little over 4 ounces each) and place on a baking sheet lined with parchment paper or a baking mat. Sprinkle on a little flaky sea salt to the tops if using.
With your oven rack in the center to top 2/3 bake at 350°F for 16-17 minutes. The edges should just be beginning to brown, but the centers will still be very soft.
Once you remove from the oven, allow the cookies to cool on the baking sheet for 6-8 minutes before transferring to a cooling rack.
This dough does not require chilling before baking. However, depending on your method of softening the butter (if you forgot to set it out and maybe melted a bit too much in the microwave), you may want to chill the dough for 30 minutes before baking. The dough should be stiff and cold before baking. If the butter was very soft, of if you are baking these in the middle of a very hot summer, chilling the dough may be necessary.