Preheat oven to 350°F. Grease an 8 or 9-inch round cake pan and line with parchment paper.
In a large bowl using a handheld mixer or stand mixer fitted with paddle attachment, cream the ¾ cup unsalted butter and 1 cup dark brown sugar until light and fluffy, Beat in the 2 eggs and 2 teaspoons pure vanilla extract.
In a separate bowl, whisk together the 2 cups whole wheat flour, 1 teaspoon baking soda, and ½ teaspoon fine sea salt. Beat this mixture into the butter mixture, then fold in the 1 ½ cups semi-sweet chocolate chips.
Press the cookie dough evenly into the prepared pan, place it in the oven, and bake for 22-30 minutes, until the top is set and golden brown and a tester comes out mostly clean.
Remove from the oven and set the pan on a wire rack to cool completely. Cut into slices and serve directly from the pan, or transfer to a plate to serve.