Pumpkin Dump Cake

Name: Pumpkin Dump Cake
Prep time: 10 min
Cook time: 1 h
Total time: 1 h 10 min
Cuisine: American, Southern
Ingredients: 1 can (15 ounces) pumpkin; 1 can (12 ounces) evaporated milk; 3 large eggs, room temperature; 1 cup sugar; 4 teaspoons pumpkin pie spice; 1 package yellow cake mix (regular size); 3/4 cup butter, melted; 1-1/2 cups chopped walnuts; Vanilla ice cream or whipped cream