Preheat oven to 350°F (175°C). Grease a 9x13-inch baking dish.
In a large bowl, whisk together pumpkin puree, evaporated milk, eggs, granulated sugar, brown sugar, cinnamon, nutmeg, ginger, and cloves until smooth.
Pour the pumpkin mixture evenly into the prepared dish.
Sprinkle dry yellow cake mix evenly over the pumpkin filling.
Add rolled oats and pecans on top of the cake mix.
Drizzle melted butter evenly over the topping.
Bake for 50–60 minutes, until the top is golden brown and set.
Allow to cool slightly before serving. Enjoy warm or at room temperature.