Preheat oven to 375 degrees. place rack in center position
whisk flour and baking soda in medium bowl and set aside
Melt 8 Tbsp butter in stainless steel frying pan over medium heat. Stir until butter browns and becomes a deep amber color. (The color or dark brown sugar). Be careful not to burn butter.
Place melted butter in large heat proof bowl. Add remaining 4 Tbsp butter and stir in until melted. Then stir in granulated and brown sugars, salt, and vanilla. Add whole egg and egg yolk and mix thoroughly. Set aside. After 3 minutes, stir again for approximately 1 minute. Wait 3 minutes and stir again for 1 minute. (this helps the sugar melt into the butter.)
Add flour mixture to butter/sugar mixture and stir until incorporated. Add chocolate chips.
Refrigerate for 30 minutes so dough stiffens somewhat.
Line baking tray with parchment paper or silpat. Portion cookies onto tray in approximately 2 Tablespoon measures.
Bake for 10 to 12 minutes until edges are golden brown but centers are still soft. Cool on baking tray for 15 minutes.
This freezes very well. I portion cookies onto silicon lined baking tray and freeze until hard. Then I can bake as needed/wanted. If baking immediately from freezer, add 2 minutes to cooking time
I found the browned butter method on Cook's Country website. I combined various recipe ideas since there are many recipes for chocolate chip cookies.
I make very small cookies - approximately 1 Tablespoon each so I can have a treat that only has 75 calories. Using a 1 Tablespoon measure makes approx 32-36 cookies.