Heat oven at 350F. Line a 8x8 baking dish with parchment paper.
Note: you can double this recipe and bake chocolate chip cookie bars in large 9x13 pan.
In a medium bowl sieve together all-purpose flour, corn starch, baking soda, baking powder, salt. Set aside.
To another large bowl add softened butter, white granulated sugar and light brown sugar.
Beat using hand blender or stand mixer or by hand using a whisk. Beat until butter and sugar are creamy.
Crack one egg into the bowl and add vanilla extract.
Beat until combined.
Add in dry ingredients to the bowl and beat until just combined.
Scoop the cookie dough from the mixer blade. Scrape sides of the bowl to mix in dry flour into the dough.
Fold chocolate chip into the cookie dough.
Transfer cookie dough to 8x8 baking dish lined with parchment paper.
Smooth into an even layer.
Pro-tip: you can sprinkle little sea salt on top of cookie dough for extra taste. Sea salt and chocolate together tastes heavenly. It’s also fun to sprinkle M&Ms on top.
Bake in pre-heated oven at 350F for 18-23 minutes. Bars are done when the edges are set and golden brown and tooth pick inserted at the center comes out almost clean.
Let chocolate chip cookie bars rest on wire rack for atleast 30 minutes or longer. Cookie bars will hold up better the longer they rest.
Cut into squares and serve!