Preheat oven to 350℉ and grease and flour a bundt pan.
In a large bowl whisk together the vegetable oil, sugar, eggs, pumpkin puree and vanilla.
1 cup vegetable oil, 1 cup sugar, 4 eggs, 1 15-ounce can pumpkin puree, 2 teaspoons vanilla extract
Add the dry ingredients and stir until everything is well-incorporated. The batter will be thick.
2 1/3 cups flour, 1 3.4-ounce packet instant butterscotch pudding mix, 1 tablespoon pumpkin pie spice, 2 teaspoons baking soda, 1/4 teaspoon salt
Pour the batter into the prepared bundt pan and spread to an even layer.
Bake for 50-60 minutes or until a toothpick poked into the center of the cake comes out clean or with a few moist crumbs.
Let cool for 30 minutes before inverting onto a wire rack.
Cool completely before frosting.