Melt butter in small saucepan on med heat and continue to simmer until browned and smelling nutty. The butter will bubble, look foamy, and then the browning will happen fairly quickly. Pay attention! Remove from heat.

Transfer brown butter to mixing bowl and whisk in both sugars. Mix until well combined and sugars have mostly dissolved into the butter. Add egg, egg yolks and vanilla. Whisk again until mixture is smooth and lightened in colour.

Whisk together flours, baking powder, baking soda and salt in separate bowl. Gently fold into butter mixture until just combined and there are no visible streaks of flour. Gently fold in chocolate chips. Cover dough and refrigerate for 2 hours.

Preheat oven to 375°F. Line cookie sheet with parchment paper. Scoop out cookie dough using a 2-inch scoop or two tablespoon measurement and place on prepared cookie sheet, spaced 2 inches apart. Bake cookies, in batches for 8-10 minutes, or until golden brown around edges. Remove cookie sheet from oven and bang 2-3 times on stove top or counter to release air bubbles. Let cookies sit on cookie sheet for 5 minutes before transferring to cooling rack.