Preheat your oven to 350°F. Spray the bottom of a 9x13 baking dish with non-stick spray and set aside.
Beat together the cake mix, buttermilk, 4 ounces of softened cream cheese and the 2 eggs with an electric mixer, until well combined.
Pour the cake batter into the pan. Bake 28 to 30 minutes or until a toothpick inserted in the center comes out clean. Set cake aside to cool.
Toast pecans by heating them in a small skillet on medium-high heat for about 4-5 minutes. Stir often. Pecans will begin to be fragrant and turn slightly darker in color. Remove from heat and cool.
In a microwave safe bowl, melt the butter and 8 ounces of cream cheese, whisk together until smooth.
Then, add in the vanilla extract and the milk, stir until combined. Next, whisk in the powdered sugar until smooth.
Using the bottom of a wooden spoon or large straw (like a smoothie straw) poke holes into the cake.
Pour the glaze all over the top of the cake spreading around as needed. Then, immediately top with the toasted pecans, sprinkle evening over the whole cake.
Refrigerate 1 hour 30 minutes. Serve and enjoy!