Heat oven to 350°. Spray your cookie sheet well with cooking spray and set aside.* Cookie sheet is the 12"x17" size. Make sure you are using a cookie sheet that has higher sides on it.
In a small mixing bowl whisk together the flour, baking soda, baking powder, cinnamon, pumpkin pie spice, nutmeg, and cloves. Set aside.
In a stand mixer (or large bowl with hand mixer) add the butter and sugar and beat for 1 minute, or until lighter in color and fluffy looking.
Add eggs, pumpkin, sour cream, milk and vanilla; beat until combined.
Add in your flour mixture and mix on low speed just until combined.
Spread the mixture evenly into your prepared cookie sheet. Bake for 20-25 minutes or until a toothpick inserted near the center comes out clean. Cool completely before frosting. * I prefer to make the cake the day before and once it's cooled, I put it in the fridge overnight. I then make the frosting and frost it the following day. It's much easier to frost a cold cake.
FROSTING : Combine cream cheese, butter, and vanilla in a mixing bowl, and beat with an electric mixer until light and fluffy. Slowly beat in the powdered sugar, one cup at a time. Continue beating until the frosting is smooth. Spread onto cake and then sprinkle with the chopped pecans.
Serve right away or refrigerate before serving. As with any pumpkin baked good, it gets better and better the longer it sits in the fridge. Keep leftovers stored in the fridge.