This casserole is my shortcut answer to Sunday-style Italian meatballs on a weeknight. I started making it after a busy fall sports season when I needed something hearty, hands-off, and universally loved. Instead of simmering meatballs for hours on the stove, a quick sear locks in flavor, and the oven brings everything together under a golden layer of mozzarella. The first time I served it, we had that quiet moment at the table where everyone takes a bite and then just nods in agreement. It felt like the perfect balance of comfort and ease.

What makes this version special is the texture. A food-processor blitz of onion, garlic, carrot, and parsley folds into the meat, giving moisture, subtle sweetness, and a fleck of fresh herbs in every bite. The combination of ground beef and hot Italian sausage brings a savory, gently spiced depth you simply cannot get from beef alone. Parmesan in the mix seasons from within, and a quick bake lets the marinara mingle with all those pan-seared bits. The cheese melts into soft, stretchy strands, and the edges go just a little bubbly and browned. It is the kind of bake that invites second helpings.

Ingredients

• Ground beef (1 lb, 85% lean): Choose beef with a little fat for juicy meatballs. 85% lean keeps them tender without greasiness and holds shape during browning.
• Hot Italian sausage (1 lb): Casings removed. Adds spice, savoriness, and fat for a succulent bite. Pork-based sausage gives classic Italian-American flavor.
• Aromatics (onion, garlic, carrot, parsley): Blitzed fine for moisture and subtle sweetness. Carrot balances acidity, while parsley adds fresh herbal lift.
• Seasoned Italian breadcrumbs (1 cup): Helps bind and absorb juices, preventing dense texture. Seasoned crumbs add gentle herbs and salt.
• Parmesan cheese (3/4 cup, grated): Salty, nutty depth throughout the mixture. Choose real Parmigiano Reggiano for best flavor and melting.
• Eggs (2 large): Bind the mixture so meatballs stay tender yet cohesive during searing and baking.
• Dried Italian seasoning (1 tsp): A quick boost of oregano, basil, and thyme. Enhances jarred marinara for a fuller flavor profile.
• Marinara sauce (24 oz): Use a favorite, like Rao’s or DeLallo. A good sauce makes the whole dish shine.
• Mozzarella (2 cups, shredded): Low-moisture, whole-milk mozzarella melts into stretchy, golden bliss without watering the sauce.
• Olive oil (1 tbsp): For searing meatballs to develop a flavorful crust and fond.
• Kosher salt and black pepper: Season to taste to balance richness and highlight the aromatics.

Instructions

Blitz the aromatics Add the onion, garlic, carrot, and parsley to a food processor. Pulse until finely chopped, stopping to scrape the sides as needed. You are aiming for small, even bits, not a puree. Fine pieces disappear into the meat and release moisture as the meatballs bake. Mix the meatball base In a large bowl, combine the ground beef, hot Italian sausage, Parmesan, salt, pepper, Italian seasoning, breadcrumbs, eggs, and the blitzed vegetables. Use clean hands to fold gently until the mixture becomes sticky and uniform. Portion into 4 to 5 ounce balls, about 8 total. Avoid compacting them too tightly to keep them tender. Brown for flavor Heat 1 tablespoon olive oil in a large skillet over medium heat. Add meatballs in batches and sear 2 to 3 minutes per side until browned. You only need to cook them about halfway; the oven will finish. Browned surfaces add depth and keep the interior juicy. Assemble the casserole Spread a few tablespoons of marinara over the bottom of a 9x13 inch casserole dish. Nestle the browned meatballs in a single layer. Pour the remaining marinara over the top and sprinkle evenly with mozzarella so every bite lands a cheesy pull. Bake to finish Lightly spray a sheet of foil with nonstick spray and cover the dish, oiled side down. Bake at 425°F for 25 to 30 minutes, until the cheese is fully melted and the meatballs reach 165°F at the center. For extra color, uncover and broil 1 to 2 minutes. Rest and serve Let the casserole rest 5 minutes to settle the sauce. Sprinkle with more chopped parsley or Parmesan if you like. Serve with garlic bread or a crisp salad to catch every drop of sauce.

Storage Tips

Cool the casserole to room temperature for 20 to 30 minutes, then refrigerate in a glass or ceramic container with a tight lid for up to 4 days. For freezing, portion meatballs and sauce into freezer-safe containers or zip bags, removing excess air. Freeze for up to 3 months. Thaw overnight in the refrigerator, then reheat covered at 350°F for 20 to 25 minutes, adding a splash of marinara if it seems dry. Individual portions reheat well in the microwave at 50 percent power so the cheese remelts gently without seizing.

Ingredient Substitutions

If you prefer mild heat, use sweet Italian sausage instead of hot, or swap in chicken or turkey Italian sausage for a lighter profile. Gluten-free breadcrumbs can replace seasoned crumbs; add 1/2 teaspoon extra salt if your substitute is unseasoned. No food processor? Grate the onion on the large holes of a box grater and finely mince the carrot and garlic. If you are out of Parmesan, use 1/2 cup grated Pecorino Romano for a saltier kick. Whole-milk ricotta dolloped on top before baking adds creaminess; use 1/2 cup in small spoonfuls.

Serving Suggestions

Bring the casserole to the table bubbling, then spoon over creamy polenta, buttered noodles, or toasted garlic bread. A peppery arugula salad with lemon vinaigrette balances the richness. For a family-style spread, add roasted broccoli or green beans and a simple tomato-cucumber salad. Garnish with chopped parsley, extra Parmesan, and a drizzle of good extra-virgin olive oil. If you are entertaining, warm a loaf of crusty bread to soak up the sauce and set out crushed red pepper for anyone who likes extra heat.

Cultural Background

This casserole nods to Italian-American red-sauce comfort, where meatballs simmered in marinara meet the practicality of a baked dish. While classic polpette in Italy are often served on their own or with lightly dressed sauces, Italian-American kitchens embraced hearty portions, tomato-rich gravies, and baked cheese. The combination of sausage and beef delivers that beloved pizzeria meatball flavor, while the oven-baked approach reflects the weeknight efficiency many families rely on. It is a bridge between old-world techniques and new-world convenience.

Seasonal Adaptations

In winter, add a pinch of crushed red pepper and a layer of sautéed mushrooms under the cheese for earthy warmth. In spring, stir in a handful of thawed peas during assembly for sweetness and color. Summer loves fresh basil; scatter torn leaves over the top right before serving. For fall, roast cubes of zucchini or eggplant and tuck them around the meatballs for a heartier, vegetable-forward bake. Adjust salt gently if your additions are seasoned.

Meal Prep Tips

Portion the mixture into meatballs and freeze raw on a lined sheet pan until firm, then transfer to a freezer bag for up to 3 months. You can brown them from frozen, adding a couple extra minutes, then bake as directed. For grab-and-go lunches, pack two meatballs with extra marinara in divided containers and keep a small bag of shredded mozzarella to add right before reheating. Always label containers with the date and reheating notes to keep weeknights effortless.

From the first sizzle in the skillet to the bubbling bake in the oven, this casserole brings reliable comfort with very little effort. I hope it becomes your go-to for busy nights, cozy weekends, and all the delicious in-betweens.