In a medium bowl combine the cake mix, melted butter, oil, and egg. The batter will be thick. Reserve ⅓ cup of the batter. Using clean hands, press the remaining dough into the bottom of the prepared baking pan.
1 box red velvet cake mix (15.25 ounce size), ½ cup butter, melted, 3 tablespoons vegetable oil, 1 large egg