Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.
Cream together the butter and sugar in a large bowl until light and fluffy.
Add the egg and vanilla extract, mixing until fully combined.
Whisk together dry ingredients: flour, baking soda, and salt. Gradually add them to the wet mixture, stirring until the dough comes together.
Roll the dough into 1-inch balls and place them on the baking sheet, leaving some space between each.
Flatten slightly with the bottom of a glass if desired, then bake for 8-10 minutes, until the edges are golden but the center is still soft.
Cool on the sheet for 2-3 minutes, then transfer to a wire rack to cool completely.
