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Pot Roast Pasta Casserole combines leftover pot roast, pasta, and mushrooms in a flavorful three-cheese sauce. This is absolutely delicious comfort food!
Make a delicious Pot Roast Pasta Casserole with leftover pot roast
My husband Jack and I both grew up in families where food never went to waste. We both hate to see perfectly good leftovers sit in the refrigerator uneaten – and that was the inspiration behind this delicious Pot Roast Pasta Casserole.
This easy pasta casserole combines the leftover meat, pasta, mushrooms, sweet onion, garlic, and a variety of cheeses including Parmesan, Provolone, and Boursin cheese, plus heavy cream, beef broth, and seasonings.
This casserole is so good – you might be tempted to cook up a pot roast just so you can make this easy and delicious meal!
Why you’ll love Pot Roast Pasta Casserole
- Every bite has savory beef and creamy cheese flavors among the tender cooked pasta.
- Leftover pot roast will never go to waste when you have this recipe in your go-to collection.
- This is a versatile recipe – make it with beef or pork, and you can add more or less meat depending on the amount of leftovers on hand.
Key Ingredients & Substitutions
- Leftover Pot Roast – We used four cups of a cooked beef pot roast in our casserole, but if you have a little more or less, that is fine (this recipe is very forgiving). You can even swap in pork pot roast if you’d like.
- Pasta – We chose a sturdy ‘mezzi rigatoni’ shape pasta which is a shorter version of a traditional rigatoni noodle. Any other larger, thick pasta (such as penne) would work.
- Mushrooms – Our casserole included Cremini mushrooms, also known as baby Bellas, which have a rich, earthy flavor. White button mushrooms can be substituted.
- Onions – We selected sweet onions for this dish, but a yellow onion can also be substituted as they both have mild flavor. We don’t recommend a white onion as the flavor is sharper and more pungent.
- Fresh Garlic
- Extra Virgin Olive Oil
- Heavy Cream
- Cheeses – We included Boursin cheese (the original Garlic and Fine Herb flavor), Parmesan cheese and sliced Provolone cheese.
- Beef Broth – Make your own or buy canned or boxed broth.
- Fresh Parsley
- Dry Mustard
- Kosher Salt
- White Ground Pepper
Special Tools Needed
- Large bowl – Used to combine ingredients
- Heavy skillet – To cook the mushrooms, onions, and garlic
- Pot – To cook the pasta
- Colander or Strainer
- Medium Saucepan – To make the cheese sauce
- Large Solid Spoon or Spatula
- 9×13-inch oven-safe casserole dish
How do I make Pot Roast Pasta Casserole?
- Sauté mushrooms, onions, and garlic in oil and butter. Once cooked, pour into large bowl.
- Add leftover pot roast pieces and provolone cheese to the same bowl, along with the chopped fresh parsley.
- Prepare sauce by melting Boursin cheese with heavy cream and Parmesan cheese. Season with salt, white pepper, dry mustard, and grated nutmeg.
- Cook pasta to slightly underdone (still a little chewy) and drain. Add pasta to the bowl with the other ingredients.
- Pour the hot cream sauce into the bowl, then stir to combine with a solid spoon or firm spatula.
- Pour the mixture into a 9x13x3-inch casserole dish that has been sprayed with non-stick spray.
- Top with grated Parmesan cheese.
- Bake for 35-40 minutes until hot and bubbly with some browning on top.
- Serve immediately with additional chopped parsley over the top.
Tips & Tricks
If needed, heat the bowl with the meat, vegetables, and provolone in the microwave for a few minutes to get everything hot before adding the cream sauce and pasta. This will make the mixing a little easier.
Frequently Asked Questions
- Can I make Pot Roast Casserole ahead of time? Yes – you could cook and cool each component (meat, pasta, vegetables, and the sauce). Heat each of them back up before assembling and baking the casserole. Or, bake ahead of time and reheat in the oven when ready to eat.
- How do I store leftovers? Assuming your leftover pot roast was freshly made, store the leftover casserole covered in the refrigerator for up to three days. (If your leftovers are more than a day old, the casserole will stay fresh for less time.)
- How do I reheat leftovers? Heat individual portions in the microwave. Or place the casserole dish back into the oven to heat through. You may want to cover with foil to avoid drying out the pasta.
- Can I freeze? We don’t recommend freezing this casserole.
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2 tablespoons butter, divided
2 tablespoons olive oil, divided
12 ounces Cremini mushrooms, quartered if large or halved if small
2 cups sweet onion, diced large
1 tablespoon fresh garlic, minced
4 cups leftover pot roast, cubed
1/2 pound provolone cheese slices, cut up
1/4 cup fresh parsley, chopped, plus more as garnish
12 ounces dry Mezzi Rigatoni
1/2 cup beef broth (either leftover from pot roast or canned or boxed broth)
1 cup heavy cream
2 5.2-ounce containers of Boursin cheese, garlic and fine herb flavor
1 1/2 cups freshly grated Parmesan cheese, divided
1/2 teaspoon kosher salt
1/4 teaspoon white pepper
1/2 teaspoon dry mustard
Few grinds fresh nutmeg
- Spray a 9x13x3-inch casserole dish with non-stick spray and preheat the oven to 375 degrees F.
- Melt one tablespoon of butter in one tablespoon of oil in a high heat pan such as cast iron or carbon fiber over medium high heat. Once hot, add mushrooms and cook for about ten minutes stirring often until well browned. Remove to a large bowl.
- Add remaining butter and oil to the pan and reduce heat to medium and add the onions.
- Cook onions for about five minutes or until they start to get soft then add garlic and cook for one minute. Add to large bowl with the mushrooms.
- Add the cut-up pot roast along with the parsley and provolone to the large bowl then toss to combine.
- Heat the bowl of meat and vegetables in the microwave for a few minutes to get the heat up and to accommodate the sauce and pasta.
- Place a large pot of water on to boil and once boiling, salt the water and add the pasta. Cook shy of fully cooked since the pasta will cook further in the oven and absorb some of the sauce.
- While the pasta cooks, in a medium sauce pan, heat broth, cream, Boursin cheese, one cup of the Parmesan cheese, salt, pepper, dry mustard and nutmeg and cook just to melt and combine. Remove from heat and add to the large bowl.
- Once the pasta is cooked, drain and add to the bowl with the other ingredients and stir to combine.
- Pour into the prepared casserole dish and cover with the remaining half cup of Parmesan cheese and bake for 35-40 minutes uncovered or until hot and bubbly and slightly browned on top.
- Serve immediately with more chopped parsley as garnish.
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