Leave butter at room temperature for 1 hour until softened, then whip it using a whisk.

Add salt, white sugar, and brown sugar, and continue mixing with the whisk.

Add 1 egg (also left at room temperature for 1 hour) and mix well.

Add peanut butter and mix until well combined.

Sift cake flour, baking soda, and baking powder into the mixture and combine.

Mix until no dry flour is visible and the dough forms a single mass.

Roll the dough into balls about 3cm in diameter using your hands.

Use a fork to create a crisscross pattern on the cookies, or flatten them with your palm.