Preheat oven to 375. Line cookie sheet with parchment paper.
If using softened butter, place in mixing bowl with the softened cream cheese. Beat several minutes until light & fluffy.
If you’re using melted butter: slightly melt the butter in the microwave, set aside to cool. (Slightly means not all the way melted; while cooling, the rest of the butter will melt). Put the room temp cream cheese in a mixing bowl & poor the cooled butter over it. Mix until smooth & creamy.
In a medium bowl, whisk together the flour, baking soda, salt & cinnamon; set aside. See notes on measuring flour. (1)
To the butter & cream cheese mixture, add the brown sugar & granulated sugar. Beat on medium speed for 2 – 3 minutes until well combined & fluffy. If you’re using softened butter, mix until creamy & well combined.
Add the egg yolks, one a time, beating on low for one minute & then add the vanilla until blended.
Add the flour mixture 1/3 at a time, mixing on low until combined. Scrape down the sides and up from the bottom of the bowl. Repeat until the flour has been well combined. (8)
Stir in the chocolate chips, chopped dark chocolate & pecans until well combined.
Cover the mixture & refrigerate for at least 4 -24 hours. Super important! Why: (9)
Remove from frig & bake by dropping small ice cream scoops on the lined cookie sheet; approximately 2 inches apart. My favorite cookie sheet is light in color & measures 17 ½ x 13; 12 mounds of tough fit perfectly. (10)
Sprinkle with chopped Lindt dark chocolate with sea salt & give a quick turn of a sea salt grinder on top, opt.
Bake at 375 for 10-12 minutes (oven vary!) until the edges are just starting to brown. Remember cookies continue to bake while cooling. (11)
Let cool for 2-4 minutes & then remove to a wire rack.