01 - Preheat oven to 350°F. Grease a 9x13-inch baking pan thoroughly to prevent sticking.
02 - In a large mixing bowl, whisk together pumpkin puree, sweetened condensed milk, eggs, pumpkin pie spice, granulated sugar, and salt until smooth and fully blended.
03 - Pour the pumpkin mixture evenly into the prepared baking pan, spreading it smoothly across the bottom.
04 - Sprinkle the dry yellow cake mix evenly over the pumpkin layer, ensuring complete coverage without stirring.
05 - Slowly drizzle the melted butter over the surface of the cake mix, distributing it as evenly as possible. Scatter chopped pecans evenly over the top.
06 - Bake in the preheated oven for 45 to 55 minutes, or until the top is golden brown and the center appears set.
07 - Allow the cake to cool for at least 30 minutes before slicing. Serve warm or chilled, optionally garnished with whipped cream or vanilla ice cream.