Preheat your oven to 375°F (190°C).
In a large skillet over medium heat, brown the ground beef until fully cooked. Drain any excess fat.
Stir in the ranch seasoning mix, sweet corn, sour cream, milk, salt, and pepper. Simmer for 3-5 minutes.
Add the cooked rotini pasta to the skillet and mix well until everything is evenly combined.
Transfer the mixture into a greased 9x13 inch baking dish.
Top evenly with shredded cheddar cheese.
Bake for 15-20 minutes, or until the cheese is melted and bubbly.
Garnish with chopped parsley if desired. Serve warm.