1. Bring a large pot of salted water to a boil. Add rotini and cook until just under al dente, about 7–8 minutes. Drain and set aside.

2. In a skillet over medium-high heat, brown the ground beef. Add diced onion and cook until softened. Stir in garlic and cook 30 seconds more.

3. Add marinara sauce, salt, pepper, Italian seasoning, and red pepper flakes. Simmer on low for 10 minutes.

4. In a separate saucepan, melt Velveeta with milk and butter over low heat, stirring until smooth.

5. In a large bowl, combine drained pasta, beef marinara, and cheese sauce. Stir until evenly coated.

6. Preheat oven to 375°F (190°C). Transfer pasta mixture to a greased 9×13-inch baking dish.

7. Top with shredded mozzarella. Cover with foil and bake for 20 minutes.

8. Uncover and bake an additional 8–10 minutes until cheese is golden and bubbly. Broil for 1–2 minutes if desired.

9. Let rest for 5 minutes before serving. Garnish with parsley and optional parmesan.