Preheat the oven to 350°F.
Lightly butter a 9x13 or 15x10 inch baking dish. Set aside.
In a large mixing bowl, combine flour, sugar, baking powder, cinnamon, baking soda, salt, cloves, and nutmeg; whisk until well combined.
Using a spoon, stir in the eggs, pumpkin, oil, and vanilla until thoroughly incorporated.
Pour batter into previously prepared baking dish; spread evenly.
Bake for 25 to 30 minutes, or until a toothpick inserted in the center comes out clean.
Remove from oven and transfer pan to a wire rack; cool in pan for 2 hours.
Spread prepared cream cheese frosting on top. Recipe to follow.
Cut into bars and serve.
Cover leftovers and keep refrigerated for 5 days.