French Onion Ground Beef and Rice Casserole is rich, cozy comfort food that tastes like French onion soup collided with a cheesy beef and rice bake. Tender ground beef, fluffy rice, and sweet onions soak up savory beef broth and French onion flavors, then get finished with a layer of gooey cheese and crispy fried onions on top.
It’s buttery, beefy, and packed with oniony goodness, with just enough crunch from the topping to keep every bite interesting. This casserole is simple to throw together but feels special enough for a Sunday dinner, and it reheats beautifully for easy leftovers.
Equipment
- Large skillet
- 9×13-inch baking dish
- Mixing bowl (optional)
- Measuring cups and spoons
- Aluminum foil
Ingredients
- 1 pound ground beef
- 1 medium onion, diced
- ½ teaspoon salt
- ½ teaspoon black pepper
- 1 packet (about 1 ounce) dry onion soup mix
- 2 cups instant white rice, uncooked
- 2 cups beef broth
- 1 can (10.5 ounces) French onion soup
- ½ cup sour cream
- 2 cups shredded mozzarella or Swiss cheese
- 1 cup crispy fried onions
- Chopped fresh parsley, for garnish (optional)
Instructions
To make French Onion Ground Beef and Rice Casserole, start by building the beef and onion base. Preheat your oven to 350°F (175°C) and lightly grease a 9×13-inch baking dish so the rice and cheese don’t stick.
In a large skillet over medium-high heat, add the ground beef and diced onion. Cook, breaking the meat apart with a spoon, until the beef is fully browned and the onion is soft and translucent. Drain off any excess grease so the finished casserole isn’t oily.
Sprinkle the salt, pepper, and dry onion soup mix over the cooked beef and onions. Stir well until the beef is evenly coated with the seasoning; you’ll see the onion soup mix clinging to the meat and lightly tinting the juices. Turn off the heat and let the mixture sit for a couple of minutes so the flavors start to absorb while you get the rest of the casserole ready.
In the prepared baking dish, spread the uncooked instant rice into an even layer. Pour the beef broth and French onion soup over the rice, then add the sour cream.
Whisk or stir carefully right in the dish until the liquids and sour cream are blended into a creamy, brothy mixture and the rice grains are evenly distributed. This is the bath the rice will cook in, and it’s loaded with savory French onion flavor from both the canned soup and the dry mix on the beef.
Spoon the seasoned ground beef and onion mixture over the rice and broth layer, spreading it out evenly all the way to the edges.
Use the back of the spoon to gently press the beef down so some of it sinks into the liquid; you want the meat nestled among the rice rather than floating on top so everything cooks together and the flavors meld. Don’t worry if a little beef is still visible on top—some will still brown and add extra flavor.
Cover the baking dish tightly with aluminum foil, making sure it’s sealed around the edges so steam and moisture stay trapped inside. Place the dish on the center rack of your preheated oven and bake for about 30–35 minutes.
During this time, the rice will absorb the broth and soup mixture, softening and swelling, while the beef infuses that liquid with extra richness. Try not to peek or remove the foil early, as releasing steam can slow down the cooking and leave the rice underdone.
After 30–35 minutes, carefully remove the casserole from the oven and lift a corner of the foil away from you to let the steam escape safely. Check the rice by gently fluffing a small area with a fork; it should be tender and most of the liquid should be absorbed.
If the rice still looks firm or you see a lot of liquid, re-cover and bake for another 5–10 minutes, then check again. Once the rice is cooked through and the mixture looks creamy and cohesive, remove the foil completely.
Sprinkle the shredded cheese evenly over the surface of the hot casserole. Use the full two cups if you like a thick, extra-gooey top; you can use a little less if you want it lighter. Then scatter the crispy fried onions over the cheese in an even layer.
The cheese will melt onto the casserole and help hold the crispy onions in place, while the onions add crunch and a concentrated hit of French onion flavor.
Return the uncovered casserole to the oven and bake for another 10–15 minutes, or until the cheese is fully melted and bubbling and the fried onions are golden and toasty.
Keep an eye on the topping toward the end of the baking time; if your oven runs hot, the onions can brown quickly. If they look like they’re getting too dark before the cheese is fully melted, you can loosely tent the top with foil for the last few minutes.
When the top looks bubbly and golden, remove the casserole from the oven and let it rest on the counter for about 10 minutes. This short rest allows the rice to finish setting and makes it easier to scoop neat servings without everything sliding apart.
Sprinkle chopped parsley over the top if you like a bit of color and freshness, then use a large spoon to serve generous portions, making sure each scoop includes plenty of beef, rice, melted cheese, and crispy onion topping.
Tips & Variations
This casserole is very forgiving and easy to adapt. Instant rice keeps things convenient and ensures everything cooks at the same rate in the oven, but if you prefer regular long-grain rice, you’ll need to par-cook it slightly on the stovetop before combining it with the beef and liquids so it doesn’t stay crunchy.
Just cook it about halfway in broth, then stir it into the baking dish with the soup and sour cream and extend the oven time as needed until it’s tender. The goal is always soft, fluffy rice that’s fully saturated with the beefy, oniony sauce.
You can deepen the “French onion” flavor by adding extra onions or caramelizing part of them. Instead of just softening the diced onion with the beef, you can start them alone in a bit of butter over medium-low heat, cooking slowly until they turn deep golden and sweet before adding the beef to brown.
This adds another layer of flavor that’s very reminiscent of true French onion soup. A splash of Worcestershire sauce or a few dashes of soy sauce in the beef mixture can also add savory depth.
Cheese choice makes a difference in the overall character of the casserole. Mozzarella will melt beautifully and give you long, stretchy cheese pulls with a mild flavor, while Swiss, Gruyère, or a mix will lean more into the French onion soup vibe with a nuttier, slightly sharper taste. You can also sprinkle a bit of Parmesan under or over the main cheese layer if you want a more pronounced salty, tangy note.
If you want to add vegetables directly into the casserole, you can stir in a handful of sliced mushrooms, bell peppers, or even frozen peas along with the beef and rice mixture.
Just be aware that juicy vegetables can release some extra moisture, so if you add a lot, you may need to slightly reduce the broth to keep the finished dish from getting too wet. Mushrooms pair particularly well with French onion flavors and can be sautéed with the beef and onions to cook off their moisture before baking.
For a creamier version, you can increase the sour cream or stir in a little bit of cream cheese with the liquids before adding the beef and rice. This will make the base more like a French onion–flavored creamy casserole rather than a straightforward rice bake, and it can be especially appealing if you like very rich dishes.
On the other hand, if you prefer a lighter feel, you can reduce or omit the sour cream and rely more on broth and soup, then serve the casserole with a crisp salad to balance the richness.
If you enjoy a touch of heat, a pinch of red pepper flakes stirred into the beef mixture or a drizzle of hot sauce at the table brings a little kick that contrasts nicely with the sweetness of the onions and the richness of the cheese. You can also experiment with herbs—dried thyme, rosemary, or a bay leaf simmered in the broth before baking can give more complexity to the underlying flavor.
Serving & Storage
French Onion Ground Beef and Rice Casserole is hearty enough to stand on its own, but it pairs nicely with a few simple sides. A crisp green salad with a light vinaigrette cuts through the richness and gives you some fresh crunch alongside each creamy, cheesy bite.
Steamed or roasted vegetables like green beans, broccoli, or Brussels sprouts also make good partners and help round out the meal. If you’re feeding a crowd, warm dinner rolls or garlic bread are always welcome for swiping up any extra sauce left on the plate.
Leftovers keep very well and reheat easily, which makes this casserole a solid choice for meal prep or next-day lunches. Let the dish cool to room temperature, then cover tightly or transfer portions to airtight containers and refrigerate for up to three or four days.
To reheat a larger portion in the baking dish, cover it with foil and warm in a 325°F (165°C) oven until heated through, then uncover for a few minutes to re-crisp the fried onion topping if you’d like. Individual servings can be reheated in the microwave in short bursts, stirring or rotating halfway for even heating; the topping will soften a bit but the flavors will still be great.
You can also freeze this casserole, though the crispy onions will lose some crunch after thawing. For best results, assemble and bake the casserole up to the point of adding the fried onions and cheese, then cool, wrap tightly, and freeze.
When you’re ready to serve, thaw overnight in the refrigerator, reheat covered until hot, then add fresh cheese and crispy onions on top and bake uncovered until the cheese melts and the onions are golden. Even if you freeze leftovers with the topping already on, the casserole will still be delicious; just know the onions will be softer. Either way, this dish holds its flavor well and makes an easy, satisfying dinner whenever you need it.
