Place dark brown sugar and a small bowl and stir in the molasses and granulated sugar, making sure there are no lumps.
Cream together butter and all sugars until light and fluffy in a stand mixer fitted with a paddle attachment.
Add in eggs to the butter/sugar mixture and incorporate fully.
Combine all dry ingredients together in a bowl: baking soda, salt, and Cup4Cup flour. Incorporate in to creamed butter and eggs, in 2 additions, mixing on low speed.
Fold in chocolate chips and chunks into the dough. Refrigerate the dough for 30 minutes.
Scoop cookies of desired size onto a silpat or parchment lined sheet trays.
Bake at 325 degrees until golden brown, about 10 minutes.