Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper or a silicone baking mat.
In a large bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy.
Beat in the eggs one at a time, then stir in the vanilla extract until fully combined.
In a separate bowl, whisk together the all-purpose flour, cream of tartar (if using), and salt.
Gradually add the dry ingredients to the wet ingredients, mixing just until combined—avoid overmixing.
Fold in the chocolate chips evenly throughout the dough.
Scoop tablespoon-sized portions of dough onto the prepared baking sheet, spacing them about 2 inches apart.
Bake for 10-12 minutes, or until the edges are lightly golden but the centers remain soft.
Remove from the oven and let the cookies cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.