Preheat and Prepare Pan (5 minutes)
Preheat your oven to 350°F (175°C). Grease a 9×13‑inch baking dish lightly with butter or nonstick spray.
Make Pumpkin Layer (5 minutes)
In a large bowl, whisk together pumpkin puree, evaporated milk, eggs, sugar, pumpkin pie spice, vanilla, and salt. Stir until smooth and creamy.
Pour into Dish (1 minute)
Pour the pumpkin mixture into the prepared baking dish—smooth surface with a spatula.
Add Crunch Topping (2 minutes)
Evenly sprinkle the dry cake mix over the pumpkin layer. Drizzle melted butter evenly over the cake mix—don’t stir. Optionally scatter chopped nuts on top for extra crunch.
Bake (50 minutes)
Bake at 350°F for about 50 minutes, until the top is golden brown and crunchy and the pumpkin layer is set (it should jiggle only slightly).
Cool Completely (1 hour)
Remove from oven and let cool on a rack for at least 1 hour—this helps the topping crisp up and the filling to stabilize.
Chill (Minimum 2 hours)
Refrigerate the pumpkin crunch uncovered or lightly covered. Chill at least 2 hours, ideally overnight, for best texture.