Preheat the oven to 350°F on low fan. Line a 8”x 8” pan with aluminum foil, pressing foil into the pan, allowing foil to overlap the pan by 1-2 inches. Spray foil liberally with pan spray. Place butter in a medium saucepan over low heat. Allow butter to slowly brown. This will require stirring and careful watching. Do not burn butter. When brown, remove butter o the stove and transfer to a mixing bowl. Quickly add in sugars, vanilla and instant coee. Stir to blend. Add eggs to the mixture one at a time, beating vigorously for 2-3 minutes. Add flour and cocoa together. Then add to the wet mixture and mix until combined, but do not over mix. The goal is to make sure the batter is not over-mixed when the flour is incorporated. Fold in about 2⁄3 of the dark chocolate chunks. Pour into the prepared pan and spread evenly to the edges. Sprinkle on the remaining chocolate chunks. Bake for 30 minutes for extra gooey, 35 minutes for fudgy and 40 minutes for less fudgy. Cool to room temperature in the pan. Refrigerate for 30 minutes to 1 hour. Remove from the refrigerator and pull the foil lining with the brownies out. Using a heated knife, to make sure you get clean edges, mark and cut into 16 even pieces per pan. Store at room temperature in an airtight container until needed.