Prepare the Meatball Mixture: Start by combining ground meat, breadcrumbs, egg, garlic, parmesan, parsley, salt, and pepper in a bowl. Mix gently until everything comes together without overworking it, since that keeps the meatballs soft. Roll into small, even balls so they cook evenly later.
Cook the Meatballs: Heat a pan with a little oil over medium heat. Add the meatballs and cook until browned on all sides. They do not need to cook fully through at this stage since they will finish in the oven. Set them aside once they develop a nice golden crust.
Boil the Pasta: Bring a large pot of salted water to a boil and cook the pasta until just slightly underdone. This step matters because the pasta will continue cooking in the oven and soak up the sauce without turning mushy.
Build the Sauce Base: In the same pan, heat olive oil and sauté the chopped onion until soft and fragrant. Pour in the marinara sauce and sprinkle in Italian seasoning. Let it simmer for a few minutes so the flavors blend nicely.
Combine Everything: Add the cooked pasta and meatballs into the sauce, gently mixing so everything gets coated. Make sure the sauce reaches into every corner, giving each bite that rich flavor.
Assemble the Bake: Transfer the mixture into a baking dish and spread it out evenly. Sprinkle mozzarella and cheddar or parmesan over the top, covering the surface generously for that golden finish.
Bake Until Bubbly: Place the dish in a preheated oven at 180°C and bake for about 20 to 25 minutes. Watch for the cheese to melt and turn lightly golden, with sauce bubbling around the edges.
Rest and Serve: Let the bake sit for a few minutes after taking it out. This helps everything settle and makes serving easier. Scoop into bowls while still warm and gooey.
