Preparation Steps

• Preheat oven to 350°F (175°C). Lightly grease a 9x13-inch baking dish.
• Bring a large pot of salted water to a boil and cook the spaghetti according to package directions until al dente. Reserve 0.5 cup of pasta water, then drain the pasta.
• While the pasta cooks, heat olive oil in a large skillet over medium heat. Add the chopped onion and cook until softened, about 4 minutes. Add the minced garlic and cook 30 seconds until fragrant.
• Add the ground beef to the skillet, breaking it up with a spoon. Cook until browned and no longer pink, about 6–8 minutes. Drain any excess fat.
• Stir in the drained diced tomatoes and Italian seasoning. Simmer for 3–4 minutes to combine flavors. Season with salt and black pepper to taste.
• In a large bowl, beat together the softened cream cheese and sour cream until smooth. Stir in 1.0 cup of shredded cheddar and add a splash of reserved pasta water if needed to loosen the mixture.
• Combine the cooked spaghetti with the cream cheese mixture and half of the meat mixture; toss until the pasta is evenly coated. Transfer the coated pasta to the prepared baking dish.
• Top the pasta with the remaining meat mixture, then sprinkle the remaining 1.0 cup of shredded cheddar evenly over the top.
• Bake in the preheated oven for 15–20 minutes, until the cheese is melted and bubbly. Broil 1–2 minutes if you want a golden top—watch carefully to avoid burning.
• Remove from the oven and let rest 5 minutes. Garnish with sliced green onions and serve warm.