Preheat oven to 350 degrees. Combine the cake mix, egg and butter and mix well with an electric mixer. Pat the mixture into the bottom of a lightly greased 13”x9” baking pan. To make the filling: In a large bowl, beat the cream cheese and pumpkin until smooth. Add the eggs, vanilla, and butter, and beat together. Next, add the powdered sugar, cinnamon, nutmeg, and mix well. Spread pumpkin mixture over cake batter and bake for 40 to 50 minutes. Make sure not to overbake as the center should be a little gooey. Serve with fresh whipped cream.   Variations: For Pineapple Gooey Cake: Replace pumpkin with 20 ounce can of crushed pineapple. For Banana Gooey Cake: Replace pumpkin with 2 ripe bananas. For Peanut Butter Gooey Cake: Replace pumpkin with 1 cup creamy peanut butter and replace yellow cake mix with chocolate cake mix.