Preheat the oven to 350°F (175°C) and line two baking sheets with parchment paper.

In a large mixing bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy, about 2 minutes.

Beat in the eggs, one at a time, mixing well after each addition. Stir in the vanilla extract.

In a separate bowl, whisk together the flour, baking soda, salt, and cornstarch.

Gradually add the dry ingredients to the wet mixture, mixing until just combined. Do not overmix.

Fold in the white chocolate chips, dried cranberries, and chopped pecans (if using).

Scoop tablespoon-sized portions of dough onto the prepared baking sheets, spacing them 2 inches apart.

Bake for 9–11 minutes, or until the edges are golden and the centers look set but slightly soft.

Let the cookies cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.