Preheat the oven to 350°F. Grease a 9x13-inch baking dish.
In a large bowl, whisk together pumpkin purée, evaporated milk, eggs, brown sugar, pumpkin pie spice, and salt until smooth. Pour into the prepared baking dish.
In a medium bowl, beat softened cream cheese, ¼ cup sugar, and vanilla until smooth and creamy.
Drop spoonfuls over pumpkin mixture, then lightly swirl with a knife for a marbled effect.
Sprinkle dry spice cake mix evenly over the top.
Sprinkle white chocolate chips evenly, followed by chopped pecans.
Slowly drizzle melted butter evenly over the top, covering as much dry mix as possible.
In a small bowl, mix 2 tablespoons sugar with ½ teaspoon cinnamon.
Sprinkle evenly over the entire cake.
Place in the oven and bake for 50–55 minutes, or until the top is golden brown and the edges are bubbling.
Let cool at least 15 minutes before serving.