Preheat oven to 350 and line cookie sheet with parchment paper

Sift together the flour, cornstarch, baking powder, baking soda, salt and set aside

In a separate bowl or stand up mixture cream together the room temp butter, both sugars , eggs and vanilla. Blend until smooth and fluffy

Add the flour mixture to the butter mixture a little at a time until all of it is incorporated

Fold in chocolate chips

I used a 1 1/2 tablespoon cookie scoop and place the mounds of cookie dough about 2 inches apart

Bake 11-13 minutes depending on your oven-the edges should be slightly brown

cool on a wire rack