Preheat your oven to 350°F (175°C).

Cream together softened butter, granulated sugar, and brown sugar in a large mixing bowl until light and fluffy.

Add the room-temperature egg and mix until well combined.

In a separate bowl, whisk together flour, baking powder, and salt, then gradually add to the wet ingredients, mixing until just combined.

If the dough is sticky, chill it in the refrigerator for 20-30 minutes.

Drop rounded balls of dough onto a baking sheet lined with parchment paper, leaving 2 inches of space between each.

Bake for 10-12 minutes until golden around the edges, but the centers remain soft.

Cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.