Preheat the oven to 375 degrees F, and line a baking sheet with parchment paper.
Mix the butter and sugars together in a mixing bowl until a grainy substance has formed (around 1 to 2 minutes). Add the egg and vanilla and mix until combined.
In a separate bowl mix together the dry ingredients: salt, flour, baking soda, baking powder, cornstarch.
Pour the dry ingredients into the wet ingredients and mix until just combined. Fold in the chocolate chips/chunks.
Use a 2-inch cookie scoop to scoop out the cookie dough and roll by hand into round balls and rip cookie balls in half. Put back together, but with the jagged edge facing upward on the cookie sheet (you can skip this step and just roll them if you wish).
Bake in the oven for 10 minutes. Don’t overcook! You want them to be soft and yummy. Let cool on the baking sheet for 8 minutes and then transfer to a cooling rack. Enjoy!