Easy Stuffed Pepper Casserole Recipe

Classic stuffed peppers are wonderful — right up until you are hollowing out peppers, par-cooking them, stuffing them one by one, and hoping they stand up in the pan. This stuffed pepper casserole skips all of that. You chop the peppers into big, chunky pieces, stir them straight into a skillet with seasoned ground beef, rice, and a rich tomato sauce, blanket the whole thing with mozzarella, and let the oven finish the job. Same cozy flavor, a fraction of the work.

Look at the photo and you will see exactly what you get: glossy red, yellow, and green pepper pieces that still hold their shape, savory beef and tender rice in every scoop, and that golden, stretchy cheese top with a shower of fresh parsley. It is a true scoop-and-serve dinner — no pepper boats, no filling spilling everywhere, just big spoonfuls of comfort in a bowl.

Why This Casserole Beats Stuffing Peppers One by One

• No stuffing, no fuss — the peppers go in chopped, not hollowed and filled. You save at least 20 minutes of fiddly work.
• One skillet, stove to oven — everything cooks in a single oven-safe skillet, so there is barely anything to wash.
• Peppers in every bite — chopped peppers are mixed through the whole casserole instead of sitting in one shell you may or may not finish.
• That melty cheese blanket — a full layer of mozzarella melts down into every scoop, just like the photo.
• Leftover rice’s best job — this is the perfect home for the cooked rice sitting in your fridge right now.

The Ingredients (Pantry Staples, Rainbow Peppers)

• 1 tablespoon olive oil — for browning the beef and getting the skillet nice and hot
• 1 pound (450 g) ground beef, 85% lean — flavorful and meaty; drain it well so the casserole stays rich, not greasy
• 1 medium yellow onion, diced — it softens into the sauce and adds sweetness underneath everything
• 3 large bell peppers (about 1 1/2 pounds / 680 g), mixed colors, cut into chunky 1-inch pieces — red, yellow, and green are the mix in the photo. Big pieces hold their shape and stay tender-crisp instead of melting away
• 3 cloves garlic, minced — added near the end of the sauté so it stays fragrant, not bitter
• 1 tablespoon tomato paste — a small amount with a big job: it deepens the tomato flavor and gives the sauce its rich color
• 2 teaspoons Italian seasoning — the classic stuffed-pepper herb blend, all in one jar
• 1 teaspoon salt, plus more to taste — season in layers and check again before the cheese goes on
• 1/2 teaspoon black pepper
• 1 can (14.5 oz / 410 g) diced tomatoes, with their juices — they keep the sauce chunky and bright
• 1 can (8 oz / 227 g) tomato sauce — pulls everything together into a proper scoopable sauce
• 2 cups cooked long-grain white rice — leftover or freshly cooked both work; day-old rice is ideal because the grains stay separate
• 2 cups (about 8 oz / 225 g) shredded mozzarella cheese — the pale, stretchy blanket on top of the photo. Shred it from a block if you can; it melts smoother
• 1/4 cup chopped fresh parsley, for serving — that bright green finish scattered over the top, exactly like the photo

How to Make It: Brown, Sizzle, Simmer, Bake

1. Heat the oven and brown the beef. Set the oven to 375°F (190°C). Heat the olive oil in a large, deep oven-safe skillet (a 12-inch cast iron skillet is perfect) over medium-high heat. Add the ground beef and cook for 6 to 7 minutes, breaking it into crumbles, until well browned with no pink left. Drain off the fat and return the beef to the skillet.
2. Soften the onion and peppers. Add the diced onion and the chunky pepper pieces to the beef. Cook for 5 to 6 minutes, stirring now and then, until the onion is soft and the peppers are just starting to soften at the edges — they should still look bright and hold their shape, like the photo. Stir in the garlic and cook 30 seconds, until fragrant.
3. Bloom the seasonings and tomato paste. Sprinkle in the Italian seasoning, salt, and black pepper, and stir in the tomato paste. Cook for about 1 minute, stirring constantly. The paste will darken slightly and coat everything — this quick step builds deep, slow-cooked flavor fast.
4. Simmer the sauce. Pour in the diced tomatoes with their juices and the tomato sauce. Stir well, bring to a gentle simmer, and cook for about 5 minutes, until the sauce thickens slightly and the peppers are tender but not falling apart.
5. Fold in the rice. Add the cooked rice and fold it through until every grain is coated in sauce and the peppers and beef are evenly mixed. Smooth the top with the back of your spoon and taste — add a pinch more salt if it needs it. Take the skillet off the heat.
6. Cheese it and bake. Shower the mozzarella evenly over the top, all the way to the edges. Transfer the skillet to the oven and bake, uncovered, for 15 minutes, until the cheese is fully melted, bubbling at the edges, and lightly golden in spots.
7. Rest, garnish, serve. Let the casserole rest for 5 minutes — this helps the scoops hold together. Scatter the fresh parsley generously over the top and serve hot, scooped into bowls just like the photo.

Sofia’s Expert Tips (Chunky Peppers, Thick Sauce, Big Cheese)

• Cut the peppers chunky — 1 inch, not a small dice. Big pieces are the whole look and texture of this dish. Small-diced peppers disappear into the sauce; chunky ones stay visible, glossy, and tender-crisp in every bite.
• Drain the beef, every time. Extra fat pools under the cheese and makes the casserole greasy. Browning well and draining gives you rich flavor without the oil slick.
• Simmer before the rice goes in. Five minutes of simmering cooks off the watery edge of the canned tomatoes. If the sauce looks thin at this stage, your finished casserole will be soupy — give it the full simmer.
• Day-old rice wins. Freshly cooked rice is soft and wet and can turn gummy in the bake. Chilled, day-old rice has firmer, drier grains that stay separate and soak up the sauce beautifully. Cooking rice just for this? Spread it on a plate and chill it for 30 minutes first.
• Shred your own mozzarella. Bagged shredded cheese is coated with anti-caking powder that makes it melt in clumps. A block shredded on a box grater takes two minutes and melts into the smooth, stretchy blanket in the photo.
• Rest it before you scoop. Five quiet minutes off the heat lets the sauce settle and thicken slightly, so your first scoop looks like the photo instead of a landslide.
• Skip the bitter bits. When you chop the peppers, cut away the white ribs and shake out the seeds. The ribs are the bitter, pithy part of the pepper, and leaving them in is the quiet reason some pepper dishes taste harsh. Thirty seconds of trimming keeps every bite sweet and clean.

Easy Variations Worth Trying

• Tex-Mex stuffed pepper casserole: swap the Italian seasoning for 1 tablespoon of taco seasoning, stir in a cup of black beans and a cup of corn with the rice, and use pepper jack cheese on top. Serve with sour cream and a squeeze of lime.
• Italian sausage version: replace half or all of the ground beef with Italian sausage (hot or sweet), squeezed out of its casings and crumbled as it browns. Richer, a little spicier, and wonderful with a handful of basil at the end instead of parsley.
• Low-carb cauliflower rice: swap the cooked rice for 3 cups of cauliflower rice. Stir it in and let it simmer 3 to 4 minutes before adding the cheese — it needs less time than regular rice and keeps the casserole hearty without the grains.
• Extra veggie-loaded: fold in a diced zucchini with the peppers and a few handfuls of baby spinach right before the cheese goes on. It wilts into the hot sauce and nobody will even notice it is there — in the best way.
• Cheesy ranch twist: stir 1 tablespoon of ranch seasoning into the sauce with the Italian seasoning and use a mozzarella-cheddar blend on top. It sounds playful because it is — and kids especially love this version.

How to Store, Freeze and Reheat It

• Fridge: cool leftovers, transfer to an airtight container (or cover the skillet), and refrigerate for up to 4 days. The flavors settle in beautifully overnight.
• Freezer: freeze in portions in airtight containers for up to 3 months. For the best cheese texture, you can freeze it before baking — assemble, cool, wrap well, and bake from thawed with about 10 extra minutes.
• Reheat in the oven: cover with foil and warm at 350°F (175°C) for 15 to 20 minutes, until bubbling. Uncover for the last few minutes to wake the cheese back up.
• Reheat in the microwave: single bowls heat in 2 to 3 minutes, stirred halfway. Add a fresh sprinkle of parsley after reheating — it makes leftovers look and taste freshly made.

FAQs

Save this recipe for the next night you crave stuffed peppers but not the project — one skillet, a shower of cheese, and dinner is scooped, served, and gone before you know it.

More recipes you’ll love: Easy Stuffed Pepper Soup, Easy Chili and Easy Cheeseburger Casserole.