After a month of very intensive R&D, I've finally come up with a decent chocolate chip cookie recipe that gives consistent results. I began with 3 classic recipes (Tollhouse, Mrs. Fields, and my favourite from the Silver Palate cookbook). For great cookies, it's not so much the ingredients that are critical, but the method. 
Scott's key tips:
1. Leave the butter to soften to room temperature, then mix with the sugars for a full 5 minutes to get a light, fluffy mixture
2. Be liberal with the salt. Chocolate and salt are natural pairings, and using a bit more than traditional recipes will make you a cookie hero.
3. Leave the finished batter to rest in the fridge for at least 24 hours.
4. Always begin baking with pans close to room temperature
5. Form individual cookies into round, golf ball shapes before baking.
300g/ 2.33 cups flour
1 tsp baking soda
1 tsp sea salt
225g/ 1 cup butter, softened to room temperature
200 g/ 1 cup, packed dark brown sugar*
170 g/ .75 cup white sugar
2 eggs
2 tsp vanilla
335 g/ 12oz/2 cups chocolate chips or couverture chocolate in small pieces
1. Combine flour, baking soda, and salt together and mix together.
2. Using a mixer, combine butter and both sugars. Add egg and vanilla. Allow to mix for 4-5 minutes on medium speed
3. Add flour mixture and mix until just combined.
4. By hand, add chocolate pieces until completely integrated into the batter.
5. Put mixture into the refrigerator for a minimum of 4 hours, ideally for 24-48 hours.
6. Preheat oven to 175C/ 350F. Do not preheat cookie sheets--they should be at room temperature to start.
7. Remove batter from refrigerator and measure out 40-50gram pieces (about 1.75oz or large ice cream scoop). Using your hands, form each cookie into a ball. Add 5-6 to the cookie sheet, allowing sufficient space between cookies and place remaining batter back in the fridge.
8. Bake for 12-15 minutes until cookies are slightly brown. Do not overbake.
9. Remove cookie sheet from oven and allow to rest for 2-5 minutes before removing
10. Continue steps 7-9 for remaining batter
*For my Swiss and German friends, brown sugar used in this recipe is an American/English product which is white sugar blended with molasses. Brown sugar is not raw sugar. To substitute, use 180grams of white sugar + 60mL of either molasses or maple syrup