Take a medium-size bowl, mix all-purpose flour, baking powder, salt, and baking soda. Whisk all ingredients well until getting combined. Now keep them aside.
By using a hand mixer or stand mixer make a creamy paste of melted butter, brown sugar, and granulated sugar for almost 5 minutes or until fluffy and light texture does not come out. Now use a rubber spatula to scrape down the side and bottom of the butter.
Now add vanilla extract and egg. Now start beating them at medium-low speed until incorporated.
Now gradually add flour mixture and beat them at medium-low speed until get mixed well.
Now take chocolate chips and mix them in a mixture by using a rubber spatula gently and slowly by hand. Do scrape the side of the bowl to incorporated any remaining flour mixture.
Take a dish wrapping sheet and cover the bowl. Keep the dough to get chill for almost 10-15 minutes, so it will get easier to handle.
Now take out the dough from the refrigerator, make 6 equal portions. Now place the mounds on a parchment paper-lined baking sheet and cover it with plastic wrap. Keep them in refrigerate for about 3 hours or up to overnight.
Preheat oven to 350°F (180°C).
Arrange 3 portion of dough on a parchement paper-lined sheetpan (make sure remaining dough still keep in refrigerator). Now bake dough inoven for about 15-20 minutes or until cookies are getting golden-brown andappear set. Don’t forget to rotate pan after 10 minutes.
Repeat the same process with remaining 3 portions of dough.
When all dough get baked, let them cooled on the sheet panfor about 10 minutes before transferring to a wire rack to cool completely, atleast 30 minutes.