In a large skillet, sauté the chopped onion in a bit of oil over medium heat until softened, about 3-5 minutes.
Add the minced garlic and ground beef to the skillet. Cook until the beef is browned and fully cooked, breaking it apart with a spatula (about 6-8 minutes).
Stir in the frozen mixed vegetables, diced tomatoes (with juices), rice, Italian seasoning, smoked paprika, salt, and pepper. Mix thoroughly and let it simmer for about 5 minutes to combine the flavors.
Transfer the beef and vegetable mixture into a greased 9x13 inch baking dish.
Sprinkle the shredded cheddar cheese evenly over the top of the casserole.
If using, crush the potato chips and sprinkle them over the cheese layer for an added crunch.
Cover the dish with aluminum foil and bake in the preheated oven for 20 minutes.
Remove the foil and bake for an additional 10-15 minutes, or until the cheese is melted and bubbly.
Let it cool for a few minutes before serving.
Notes
Serve hot straight from the baking dish, garnished with freshly chopped parsley for a pop of color. Optionally, provide a side salad for added freshness.