This French Onion Ground Beef and Rice Casserole has been a weeknight lifesaver in my home for years. I first adapted it on a rainy evening when the pantry was sparse and the kids wanted something warm and familiar. Combining a simple packet of French onion soup mix with ground beef and uncooked long-grain rice produced a casserole that smelled like dinner should: rich, savory, and a little caramelized. The creamy bite of sour cream and the melt of mozzarella or Swiss turn a basic bake into a dish people ask about again and again.

What makes this dish special is its effortless layering of textures and flavors. The rice cooks right in the casserole, absorbing seasoned beef broth and onion mix, which eliminates an extra pot and keeps cleanup minimal. I always reach for a 9x13-inch baking dish because it yields generous portions and a beautifully crisp edge where the rice meets the pan. This is the kind of family-friendly meal that arrives at the table hot and comforting, perfect for casual dinners or bringing to a potluck where you want something unfussy but satisfying.

Ingredients

• Ground beef (1 pound): Choose 80/20 for flavor and enough fat to keep the dish juicy. If you prefer leaner meat, 90/10 works but expect slightly drier texture; drain any excess grease after browning.
• Long-grain white rice (1 cup uncooked): Standard long-grain rice such as Mahatma or Uncle Ben's works well because the grains stay distinct when baked.; rinse briefly if you want less surface starch.
• French onion soup mix (1 packet): Lipton is the classic choice; it provides powdered onion, beefy notes, and dried herbs that season the entire casserole uniformly.
• Beef broth (2 cups): Use a low-sodium broth if you want tighter salt control; canned or boxed broths both work fine. For deeper flavor, use homemade or a concentrated broth diluted to 2 cups.
• Sour cream (1/2 cup): Adds creaminess and a mild tang. Full-fat sour cream yields the richest texture, but light sour cream trims calories with a modest change in mouthfeel.
• Shredded mozzarella or Swiss cheese (1 1/2 cups): Mozzarella gives a gooey stretch; Swiss adds nuttiness and a classic French onion profile. I often use a 50/50 blend for balanced flavor.
• French-fried onions (1/2 cup): The crunchy topping, such as French's crispy fried onions, provides contrast; sprinkle on at the end so they stay crisp and golden.
• Seasonings: Salt, freshly ground pepper, and a pinch of garlic powder to taste—simple seasonings sharpen the flavors without competing with the onion mix.

Instructions

Preheat and prepare dish: Preheat the oven to 350 F (175 C) and grease a 9x13-inch baking dish generously with butter or neutral oil. Proper greasing prevents sticking and helps the edges brown evenly. If you prefer, line the dish with foil for easier cleanup, leaving sides to lift the casserole out later. Brown the beef: In a large skillet over medium heat, add the ground beef and cook until browned throughout, breaking it into small pieces with a spatula. Season with 1/2 teaspoon salt, 1/4 teaspoon black pepper, and 1/4 teaspoon garlic powder while cooking. Drain excess grease to avoid an oily final dish, but leave a little fat for flavor if using lean meat. Combine rice and flavor base: In a large mixing bowl or directly in the prepared baking dish, stir together 1 cup uncooked long-grain white rice, the packet of French onion soup mix, and 2 cups beef broth until well combined. Ensure the powder is evenly distributed so the rice cooks with consistent seasoning. Incorporate beef and sour cream: Fold the cooked ground beef and 1/2 cup sour cream into the rice mixture, mixing until uniform. The sour cream helps bind flavors and creates a creamier texture as the rice absorbs the broth during baking. Assemble and top: Transfer the mixture to the greased 9x13-inch dish, spreading it evenly. Sprinkle 1 1/2 cups shredded mozzarella or Swiss cheese across the top for a uniform melt and coverage. Bake covered then uncovered: Cover the dish tightly with foil and bake in the preheated 350 F oven for 40 minutes. Remove the foil and bake an additional 10 to 15 minutes until the cheese is bubbly and the rice is tender when tested with a fork. If the cheese needs more color, broil for 1 to 2 minutes while watching carefully. Add crispy onions and finish: Sprinkle 1/2 cup French-fried onions on top and return to the oven for 3 to 5 minutes until they turn golden brown. Let the casserole rest 5 to 10 minutes before serving so the rice firms up slightly and slicing is easier.

Storage Tips

Cool the casserole to near room temperature before refrigerating to avoid raising the fridge temperature. Store in an airtight container for up to 4 days. For freezing, divide into meal-sized portions in freezer-safe containers or wrap the whole dish tightly with foil and plastic wrap; freeze up to 3 months. Reheat individual portions in the microwave covered until hot throughout, or reheat a full casserole in a 350 F oven, covered, for 20 to 30 minutes, then uncover to crisp the top for 5 to 10 minutes.

Ingredient Substitutions

If you prefer a lighter version, substitute ground turkey or a lean ground beef blend for similar texture with less fat; add 1 tablespoon olive oil when browning lean meats to replace lost fat. For a dairy-free option, use dairy-free sour cream and a plant-based shredded cheese, though the flavor profile will shift slightly. Swap long-grain white rice for jasmine if desired; increase liquid by 1/4 cup and check doneness at the 45-minute mark. For lower sodium, use a reduced-sodium French onion packet or reduce added salt and use low-sodium broth.

Serving Suggestions

Serve this casserole with a crisp green salad dressed with a lemon vinaigrette to cut through the richness, or pair with steamed green beans or roasted Brussels sprouts for a hearty dinner. Garnish with chopped parsley for color and a squeeze of lemon if you want a refreshing lift. It also pairs well with a simple bowl of mixed greens and a slice of crusty bread to mop up any leftover sauce.

Cultural Background

While inspired by classic French onion flavors popularized by soups topped with melted cheese, this casserole is an American comfort adaptation that combines efficient convenience with the beloved caramelized onion profile. It reflects the midcentury tradition of one-dish bakes that balance protein, starch, and dairy, and it often appears at potlucks and family gatherings where simplicity and warmth are prized.

Seasonal Adaptations

In colder months, serve this with roasted root vegetables and a glass of red wine for a cozy meal. In spring and summer, lighten the dish by folding in fresh herbs like chives or tarragon and serving smaller portions alongside seasonal salads. For holiday sides, add sautéed mushrooms or caramelized shallots to deepen the umami and add festive richness.

Meal Prep Tips

Make the beef mixture up to one day ahead and refrigerate. Assemble in the baking dish, cover tightly, and bake when ready. Alternatively, prepare individual portions in ramekins for grab-and-go lunches that reheat quickly. Use shallow, oven-safe containers for more even reheating and a crisper cheese topping.

Whether you are feeding a family after a busy day or bringing comfort to friends, this French Onion Ground Beef and Rice Casserole offers dependable flavor, minimal fuss, and satisfying textures. Try it as written the first time, then tweak the cheese, toppings, or meat to make it your own.