2 cups white sugar
1 1/4 cups vegetable oil
1 teaspoon vanilla extract
2 cups canned pumpkin
2 cups all-purpose flour
3 teaspoons baking powder
2 teaspoons baking soda
1/4 teaspoon salt
2 teaspoons ground cinnamon
1 cup chopped walnuts (optional)
Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 12x18 inch pan. Sift together the flour, baking powder, baking soda, salt and cinnamon. Set aside.
In a large bowl combine sugar and oil. Blend in vanilla and pumpkin, then beat in eggs one at a time.
Gradually beat in flour mixture. Stir in nuts. Spread batter into prepared 12x18 inch pan.
Bake in the preheated oven for 30 minutes, or until a toothpick inserted into the center of the cake comes out clean. Allow to cool before frosting.