Add salt, baking powder, and baking soda as well as half of your eggs, and flour. Mix for about 45 seconds on medium speed before mixer to add the remaining egg and flour, beating again for 30 seconds.
With an ice cream scoop or cookie scoop and your hand, place the cookie dough balls onto an ungreased aluminum cookie sheet (no parchment paper or silicone mat needed), with about 2 inches between them.
Transfer brown butter sugar cookies to a cooling rack after they’ve sat on the baking sheet 5 or so minutes outside of the oven and are firm enough to handle.
These cookies will stay fresh at room temperature (around 70°F) for 4 or 5 days. They also freeze well if you place them in an airtight container. Let them come to room temperature before serving.