01 - Preheat oven to 350°F. Grease a 9x13-inch baking pan thoroughly to prevent sticking.
02 - In a large mixing bowl, whisk together the pumpkin puree, sweetened condensed milk, eggs, pumpkin pie spice, granulated sugar, and salt, until the mixture is smooth and evenly combined.
03 - Pour the pumpkin mixture into the prepared baking pan and spread it into an even layer across the bottom.
04 - Evenly sprinkle the dry yellow cake mix over the pumpkin layer, ensuring complete coverage. Do not mix or stir.
05 - Drizzle the melted butter evenly over the surface of the cake mix, making sure as much of the mix as possible is moistened.
06 - Scatter chopped pecans over the top for added texture and flavor, if desired.
07 - Place the pan in the oven and bake for 45 to 55 minutes, until the top is golden brown and the center no longer jiggles. The dessert will continue to firm up as it cools.
08 - Allow to cool in the pan for a minimum of 30 minutes before slicing. Serve warm or chilled. Enhance with whipped cream or vanilla ice cream if desired.