Preheat the oven to 350°F (180°C).
In a large bowl, whisk together flour, baking soda, and salt.
In another bowl, beat the softened butter, brown sugar, and granulated sugar until creamy.
Add the egg and vanilla extract to the butter mixture, mixing until well blended.
Slowly add the dry ingredients to the wet mixture, stirring until just combined.
Fold in the chocolate chips.
Scoop the dough using a tablespoon and form into balls.
Roll each ball in crushed cornflakes before placing on a baking sheet.
Arrange the cookie balls on a baking sheet lined with parchment paper.
Bake for 10–12 minutes, or until the edges are golden.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack.