Preheat the oven to 350 degrees Fahrenheit. Spray a 9x13 baking dish with nonstick spray and set aside.
Boil a large pot of water and cook 12 oz wide egg noodles according to the package instructions until al dente.
In a separate bowl, use an electric hand mixer or stand mixer to beat the remaining filling ingredients (1 cup sour cream, 1½ cups cottage cheese, ½ cup granulated sugar, 5 eggs, ½ cup butter, ½ tsp salt, ¼ tsp nutmeg) together.
Once combined, add the pasta into the filling ingredients and hand mix until the pasta is fully coated. Pour this mixture into the prepared baking dish.
In a small bowl, pour the melted butter into 3 cups cornflakes crumbs along with 3 tbsp granulated sugar and ½ tsp cinnamon. Use a fork to mix everything together.
Sprinkle this topping over your noodle mixture in the pan.
Place your dish in the oven and cook, uncovered, for about 60-65 minutes, or until the mixture is set and the topping is brown.