Why You’ll Love Stuffed Pepper Casserole

This easy beef-and-rice stuffed pepper casserole dinner will be on your weekly meal rotation for a while.

Versatile: Swap the beef for ground turkey, add a kick of spice with red pepper flakes, or serve it as a dip with crispy tortilla chips.
Hearty: Every bite is packed with savory beef, tender veggies like peppers and onions, and perfectly cooked brown rice.
Weeknight-Friendly: Prep it ahead of time and bake it just before dinner. It’s as easy as it gets!
Italian-Inspired: Classic herbs like basil, oregano, and fennel seeds give this casserole a saucy, irresistible Italian twist.

Labeled ingredients for making stuffed pepper casserole.

What You’ll Need

Here’s a quick look at the ingredients you’ll need to throw this casserole together as well as useful ingredient swaps. For the exact ingredient amounts, please scroll to the recipe card at the bottom of the post.

Avocado oil – Feel free to use olive, coconut, corn, vegetable, or canola oil.
Ground beef – Make sure it’s completely thawed if you use frozen ground beef.
Yellow onion – White onion works too.
Bell peppers – You need red, green, and yellow ones.
Garlic – Fresh garlic, garlic paste, and garlic powder are all fine. If you use garlic powder, add 1 teaspoon of it.
Herbs – You need dried basil, oregano, and fennel seeds.
Salt and pepper – Kosher salt and freshly cracked black pepper are best.
Fire-roasted tomatoes – Regular canned tomatoes are a good swap but you’ll need to mix in 2 teaspoons smoked paprika, 1 teaspoon chipotle powder, or 1/4 teaspoon liquid smoke.
Tomato sauce – I prefer plain tomato sauce over seasoned ones because it gives you full control over the flavor.
Long-grain brown rice – Long-grain white rice is okay as well but reduce the baking time to 30-40 minutes since it cooks faster.
Beef bone broth – Try to find a low-sodium version. You can also use veggie broth or water.
Mozzarella cheese – Any melty cheese like mozzarella, Muenster, or mild cheddar will do.

Grabbing some saucy, stuffed pepper casserole with a wooden spoon.

How to Make Stuffed Pepper Casserole

This brief overview should give you an idea of how easy making this Italian stuffed pepper casserole really is. Once you add the tomato sauce and broth to the skillet, transfer everything to the casserole dish quickly so the liquid doesn’t evaporate. You will find the recipe card at the bottom of the post with more detailed step-by-step instructions.

Prep the oven. Preheat the oven to 375F. Grab a 13×9″ casserole dish and set it aside. You can also line it with parchment.
Brown the beef. Add the oil to a large skillet over medium-high heat. Add the ground beef and sautée it for 5-7 minutes or until browned.
Add the veggies. Stir in the bell peppers and onions. Cook everything for another 4 minutes or until soft and fragrant.

Pouring the stock into the skillet. — Stir gently.

Topping the casserole with shredded mozzarella. — Stir gently.

Season it. Mix in the garlic, basil, oregano, fennel, salt, and pepper. Stir to combine. Add the fire roasted tomatoes, tomato sauce, rice, and bone broth. Mix well.
Bake it. Transfer the mixture to the casserole dish. Sprinkle with mozzarella. Cover with foil and bake for 40-45 minutes or until the rice is tender and cooked through.
Serve. Remove the casserole from the oven. Let cool for 5-10 minutes. Garnish with fresh parsley and enjoy!

Baked beef and pepper casserole with melty cheese on top.

Tips and Variation Ideas

This section will help you nail a perfectly-cooked, cheesy casserole every time and even get creative with the add-ins and spices for a smokey Tex-Mex or refreshing Greek vibe.

Swap the protein. Use ground chicken, pork, or turkey instead of ground beef for an easy variation.
Make it spicy. Finely chop up 1/4-1/2 jalapeño or serrano chili and stir it into the beef-veggie mixture for a kick of heat. Adding 1/2-1 teaspoon red pepper flakes or cayenne pepper works too.
Use leftovers. Chop up leftover Cheesy Bacon Stuffed Peppers, Southwestern Turkey Stuffed Peppers, or Italian Stuffed Peppers and stir them into the skillet to reduce food waste.
Add a Greek twist. Stir 1/2 tablespoon dried dill into the veggie-beef mixture. Garnish the casserole with crumbled feta cheese, 1/4 cup sliced green olives, and 1/4 cup sliced red onions.
More veggies. Stirring 1 cup sliced mushrooms, sweet peas, or broccoli florets into the beef mixture in the skillet can help you sneak more veggies into your meals.
Go Tex-Mex. Swap the basil and fennel seeds for 3 teaspoons taco seasoning, 1/4 teaspoon ground cumin, and 1 teaspoon paprika. Mix 1/2 cup crumbled bacon, 1 cup sweet corn, and 1/2 cup black beans (strained) into the beef mixture. Top with crumbled pork rinds, sliced avocado, and Pico de Gallo.
Make it an appetizer. Turn this recipe into an appetizer by serving it with crispy Baked Pita Chips, Air Fryer Wonton Chips, or tortilla chips.

A serving plate of tomatoey beef and pepper casserole with melty cheese.

Serving Suggestions

This hearty stuffed pepper casserole is an easy weeknight dinner. I love pairing it with Bacon Green Bean Bundles and Garlic Herb Roasted Potatoes. My Instant Pot Corn on the Cob is another classic side. For quick air fryer sides to go with your meal, try my Air Fryer Asparagus and Air Fryer Green Beans. If you prefer bread, try toasted baguette slices, sourdough, focaccia, or pita bread.

How to Store and Reheat

This is a prep-friendly recipe that allows you to prep ahead for the week or even make and freeze the casserole months in advance.

Fridge: Place it in an airtight container for up to 5 days.
Freezer: Transfer the casserole to freezer bags in serving size portions. You can also cover the casserole dish tightly with foil and then wrap it with plastic wrap twice. Freeze for up to 3 months. Thaw overnight in the fridge and reheat as usual.
To reheat it: Microwave it in 20-second increments, stirring between each one until warm. You can also use the oven at 300F for 30-35 minutes.