Stuffed Pepper Casserole

This easy stuffed pepper casserole has everything I love about classic stuffed peppers, seasoned ground beef, tender rice, sweet green peppers, and melty cheese in a rich tomato sauce, all layered and baked until bubbly. It comes together in about an hour, most of it hands-off, and it makes a cozy weeknight dinner with plenty of leftovers. No hollowing out peppers, no wobbly pepper boats, just a warm scoopable casserole that tastes like comfort food.

Here is my honest confession… I have never actually liked stuffed peppers. They look a little strange standing up on the plate, and they are awkward to eat, all that cutting and chasing the filling around while the pepper tips over. I only make things I genuinely want to eat, and my husband Greg feels the same way. So when our garden gave us an overabundance of green peppers this summer, I stopped trying to force the classic version and made the dish I actually wanted instead. We turned it into a casserole. Same flavors, none of the fuss, and it’s amazing!

Why make stuffed peppers as a casserole?

A casserole solves every single thing that always bugged me about stuffed peppers. You get all the flavor of the original, but you can chop the peppers into friendly bite-size pieces instead of eating around a whole one. Every forkful has beef, rice, pepper, sauce, and cheese together, which honestly tastes better than the classic where the filling and the pepper stay a little separate.

It is also faster and more forgiving. There is no par-boiling peppers, no careful stuffing, and no worrying that the peppers will collapse in the oven. This helps because you can use peppers of any size or shape, even the lopsided ones from the garden, and nobody will ever know. When you have a big pile of green peppers to use up, this is the recipe that puts a real dent in it.

Ingredients you’ll need

Here is everything that goes into this stuffed pepper casserole. I will walk through the ones worth a note.

What kind of rice works best?

I use plain long-grain white rice here, and I cook it separately first. You want it cooked but still just barely firm, because it keeps soaking up sauce in the oven and turns perfectly tender by the time the cheese melts. One common mistake is cooking the rice all the way to soft before it goes in… then it can turn mushy after baking. If you have leftover rice in the fridge, this is a great place to use it, and it saves you a pot.

Why green peppers, and can I use other colors?

Green peppers are what I grow, and they hold up beautifully in a casserole because they stay a little firm and give that true classic stuffed-pepper flavor. If your garden or your fridge hands you red, yellow, or orange peppers, use them, whatever works for you. Just know the sweeter colors will make the whole dish a touch sweeter, which we happen to like.

Why sharp cheddar and mozzarella together?

The sharp cheddar brings the flavor, and the mozzarella brings that stretchy, gooey melt on top. Using both gives you the best of both, cheesy taste and that pull-apart cheese pull. If you only have one on hand, don’t worry, a full 2 cups of either will still be SO GOOD.

How to Make Stuffed Pepper Casserole

We’re really making this in two easy stages… cooking the rice, then building and baking the casserole. I like to start the rice first so it is ready and cooling while I work on the beef. Let’s walk through it together.

Start the rice. Cook 1 cup of long-grain white rice according to the package, but pull it off the heat a minute or two early so it stays just shy of fully tender. Fluff it and set it aside. The reason we undercook it slightly is that it finishes in the oven, and this keeps it from going soft.

Brown the beef and onion. While the rice cooks, warm a large skillet over medium-high heat and add the ground beef and diced onion. Break the beef up as it cooks, about 6 to 8 minutes, until it is browned and the onion is soft. Drain off the extra grease, but leave just a little for flavor. Stir in the garlic and cook for one more minute, until you can smell it. Be careful not to let the garlic go past golden, because it turns bitter fast.

Soften the peppers. Add your chopped green peppers right into the skillet and cook for about 5 minutes, stirring now and then. You just want them to start softening, not turn to mush… they will finish cooking in the oven. Mine are never perfectly even pieces, and it truly does not matter.

Build the sauce. Pour in the diced tomatoes with their juice, the tomato sauce, the beef broth, Worcestershire, Italian seasoning, salt, and pepper. Stir it all together and let it simmer for 5 minutes so the flavors come together. It should look saucy and a little loose right now, and that is exactly what you want, because the rice is about to drink some of it up.

Fold in the rice and half the cheese. Take the skillet off the heat and stir in your cooked rice along with 1/2 cup of the cheddar. Give it a taste and add a pinch more salt if it needs it. This is the moment to make it yours.

Assemble and top. If you’re using a baking dish, spread everything into a greased 9×13. If you browned everything in a large oven-safe cast iron skillet, even better, just level the top right in the skillet and skip the extra dish. Either way, scatter the rest of the cheddar and all of the mozzarella over the top. Don’t worry if it looks like a lot of cheese… there is no such thing.

Bake. Slide it into a 350°F oven for 20 to 25 minutes, until the cheese is fully melted and the edges are bubbling. If you want the top a little golden, pop it under the broiler for 1 to 2 minutes at the end, but stay right there and watch it, because broilers go from golden to gone in a blink (ask me how I know). Let it rest for 5 minutes before serving so it sets up enough to scoop.

How to Store and Reheat Leftovers

Leftovers keep well in an airtight container in the fridge for up to 4 days, and honestly it tastes even better the next day once the flavors settle. To reheat, microwave a single portion for a minute or two, or warm a bigger batch covered in a 350°F oven until heated through. If it looks a little dry, a splash of beef broth or water stirred in brings it right back.

You can freeze it too. Let it cool completely, then freeze in a covered dish or portions for up to 3 months. Thaw overnight in the fridge before reheating. Just know the peppers soften a bit more after freezing, which we don’t mind at all.

What to Serve with Stuffed Pepper Casserole

This is a full meal on its own, beef, rice, and veggies all in one dish, but we like a little something alongside to round it out. A simple green salad or some steamed broccoli keeps it light, and a piece of crusty bread or garlic bread is perfect for scooping up the extra sauce. On a cold night, I’ll set out a basket of my sourdough biscuits and call it done.

Frequently Asked Questions

Can I make this ahead of time?

Yes. Assemble the whole casserole, cover it, and refrigerate for up to a day before baking. Add about 10 extra minutes in the oven since it is starting cold.

Do I have to cook the rice first?

For this version, yes. Cooking the rice separately gives you the most reliable texture. Uncooked rice needs much more liquid and time, so it does not cook evenly in this casserole.

Can I use ground turkey instead of beef?

Absolutely. Ground turkey works nicely and keeps it a little leaner. Since turkey is milder, you may want a bit more salt and an extra shake of Worcestershire for flavor.

My family doesn’t love green peppers. What can I do?

Chop them a little smaller so they soften more and blend into every bite, or use half green and half red peppers to sweeten things up. Cooking them longer in the skillet mellows their flavor too.

Can I make this in a cast iron skillet?

Yes, and it saves you a dish. Brown the beef and build everything right in an oven-safe cast iron skillet, then scatter the cheese on top and slide the whole skillet into the oven. Use a large one, ideally 12 inches, so it is not overcrowded. Just remember the handle stays blazing hot coming out of the oven, so keep a towel draped over it so nobody grabs it bare-handed.

Can I make it lower-carb?

You can swap the white rice for cooked cauliflower rice. Stir it in at the end just like regular rice, and skip the extra broth since cauliflower holds more moisture.

If you have a garden bursting with peppers like mine, this is the recipe I hope you reach for first. It turned me into someone who actually looks forward to stuffed peppers, casserole-style, and I think it just might do the same for you. Let me know how it goes.

Happy cooking!

Love,
Jennifer