Preheat your oven to 350?F (177?C). Cover several baking sheets with parchment paper.

In an electric stand mixer fitted with the paddle attachment, add the peanut butter, butter, brown sugar, granulated sugar, and vanilla. Mix on medium for about 4 to 5 minutes, or until smooth and well blended.

Add in the eggs one at a time, making sure each is completely blended before adding the next. Scrape down the sides and bottom of the bowl to ensure everything is incorporated.

Add in the baking powder, baking soda, and salt. Mix for 1 minute more.

Add in the flour and mix for about 20 seconds more, or until just combined.

Add the 1/2 cup of granulated sugar to a shallow bowl.

Use a cookie scoop to portion 2 tablespoons of cookie dough and drop the dough into the bowl of granulated sugar. Gently cover in sugar and set on the prepared baking sheet, leaving 1? inches between each dough ball.

Bake one sheet at a time for 12 to 13 minutes in the center of the oven. The cookies will be very soft when they come out of the oven.

Tap the baking sheet on the counter to gently deflate the cookies and sprinkle with sea salt flakes, if using. Let them cool for 20 minutes on the baking sheet before transferring to a cooling rack.