Easy Roast Beef Noodle Casserole transforms your leftovers into a gooey pasta bake! The whole family will love this and be asking for more!
Make your life just a little bit easier by taking your leftovers and revamping them into a Casserole. This cheesy, beefy noodle dish is sure to be a hit, even with the kids, just like my Tuna Noodle Casserole and Chicken Parmesan Casserole!
Sabrina’s Roast Beef Noodle Casserole Recipe
Leftovers can be exciting when they are reimagined into an entirely new dish! Roast Beef Noodle Casserole combines simple ingredients into a decadent, rich, saucy casserole that is a complete meal in one baking dish. With similar flavors to Ground Beef Stroganoff, you won’t need sour cream to achieve a silky sauce in this casserole. The best thing about making a weekend Roast Beef or Pot Roast is having leftovers all week long! This casserole will stretch those leftovers into a hearty, beefy dinner that the whole family will love.
Recipe Card


Ingredients
- 16 ounces rotini pasta
- 2 tablespoons flour
- 2 cups beef broth
- 20 ounces condensed mushroom soup
- 2 tablespoons Worcestershire sauce
- 1 tablespoon Dijon mustard
- 2 carrots , sliced
- 2 cups mushrooms , sliced
- 2 cups leftover roast beef , cut into cubes
- 2 teaspoons dried thyme
- 1 teaspoon kosher salt
- 1/2 teaspoon coarse ground black pepper
- 1 1/2 cups Mozzarella cheese
Instructions
- Preheat oven to 375 degrees.
- Add rotini noodles to boiling water and cook 2 minutes shy of the instructions then drain and set aside.
- To the pot add the butter and flour and whisk the flour until no longer dry then cook for 1 minute.
- Add in the broth whisking until smooth.
- Cook for 5-6 minutes until thickened.
- Whisk in the condensed mushroom soup, Worcestershire sauce and Dijon mustard until smooth.
- In a large bowl mix pasta, mushrooms, carrots, beef, salt, pepper, thyme and sauce until well mixed.
- Top with mozzarella cheese and bake for 20-25 minutes until top is golden brown.
Notes
Nutrition
Notes from Sabrina
This recipe can be made entirely from scratch! Just use my easy Cream of Mushroom Soup recipe to create a homemade condensed soup. It has all the rich mushroom flavors, enhanced by onion and garlic and a buttery, creamy texture. The best part is that it freezes! So you can make a large batch and keep it on hand in the freezer for recipes like this casserole.
Table of contents
About this Recipe
A can of condensed soup provides a savory flavor and creamy texture to complement the mushrooms, carrots, and meat in this dish. This is another reason this easy leftover hack is such a great trick: you can grab a few extra casserole ingredients when shopping for your original roast beef recipe, and they will last several days until you’re ready to use them with the leftovers. You can also can use ground beef or shaved steak instead of the leftover roast beef. Simply brown the ground beef in a skillet, seasoning with salt, pepper, and a dash of onion powder. Then complete the rest of the recipe as written.
Ingredients
- 16 ounces Rotini Pasta: Curly rotini pasta is the main carbohydrate component in this casserole. You can substitute it with other pasta shapes if desired.
- 2 tablespoons Flour: Flour is used to thicken the sauce in the recipe. You can use all-purpose flour or a gluten-free alternative if needed.
- 2 cups Beef Broth: Beef broth adds a rich and savory flavor to the dish, enhancing the beefy taste. You can use vegetable broth as a vegetarian substitute.
- 20 ounces Condensed Mushroom Soup: This soup serves as the base for the casserole’s creamy sauce and contributes a mushroom flavor. You can use homemade Cream of Mushroom Soup or a different cream-based soup as a substitute.
- 2 tablespoons Worcestershire Sauce: Worcestershire sauce adds a tangy and savory flavor to the sauce. You can use soy sauce or steak sauce as alternatives.
- 1 tablespoon Dijon Mustard: Dijon mustard provides a subtle and tangy depth of flavor. You can use yellow mustard as a milder substitute.
- 2 Carrots: Carrots add a sweet and colorful element to the casserole, along with some crunch and nutrition.
- 2 cups Mushrooms: Sliced mushrooms contribute an earthy and umami flavor to the dish. You can use different types of mushrooms for variation.
- 2 cups Leftover Roast Beef: Leftover roast beef provides a hearty and savory taste. You can substitute it with cooked ground beef, chicken, or a vegetarian protein source.
- 2 teaspoons Dried Thyme: Dried thyme adds a herbal and aromatic note to the casserole. You can use other dried herbs like oregano or rosemary.
- 1 teaspoon Kosher Salt: Kosher salt seasons the dish and enhances the flavors of all the ingredients. You can adjust the amount to taste.
- ½ teaspoon Coarse Ground Black Pepper: Coarse ground black pepper adds a mild spiciness and depth to the casserole.
- 1 ½ cups Mozzarella Cheese: Mozzarella cheese is used as a cheesy topping that melts and adds a creamy texture when baked. You can use other types of cheese like cheddar or Swiss for variety.
Can this be made ahead of time?
Yes, you can prepare the casserole ahead of time. Assemble all the ingredients, cover the casserole dish with plastic wrap or foil, and refrigerate it a day in advance. When ready to bake, simply remove from the fridge and follow the baking instructions.
Pairing Suggestions
This creamy, rich noodle casserole goes perfectly with a green veggie like Roasted Broccoli or Green Beans on the side. It is also delicious served alongside a crunchy Classic Wedge Salad or with some toasty Garlic Bread.
How to Store
- Store: Casserole can be kept warm for up to two hours before needing refrigeration. Since you are using leftover meat, keep the casserole in an airtight container for up to 3 days maximum.
- Reheat: To reheat, cover it with foil to prevent drying out, and place it in a preheated oven at 350°F (175°C) for about 15-20 minutes or until heated through. Alternatively, you can microwave individual portions for 2-3 minutes, ensuring even heating.
- Freeze: This casserole is very freezer-friendly and can be frozen, tightly wrapped, for up to 4 months. Perfect for meal prepping!
Slow Cooker Method
- In a large skillet, follow the original recipe’s instructions for making the sauce (flour, butter, broth, mushroom soup, Worcestershire sauce, and Dijon mustard). Cook until it thickens.
- In your slow cooker, layer the ingredients as follows: first, spread a thin layer of the sauce on the bottom, then add a portion of cooked pasta, sliced mushrooms, sliced carrots, cubed roast beef, and a sprinkle of dried thyme, salt, and pepper.
- Repeat the layers until all the ingredients are used, ending with a layer of sauce on top.
- Cover the slow cooker and cook on low for 3-4 hours or on high for 1-2 hours, until the casserole is heated through and the flavors meld together.
- In the last 30 minutes of cooking, top the casserole with Mozzarella cheese and let it melt.
- Serve directly from the slow cooker when ready.
Frequent Questions
Yes, you can substitute rotini pasta with your preferred pasta shape, but adjust the cooking time accordingly to ensure it’s slightly undercooked before draining.
If you don’t have leftover roast beef, you can use cooked ground beef, chicken, or even a vegetarian protein source like tofu or beans. Feel free to use just about any leftover meat, like chuck roast, or poultry.
Certainly, you can use gluten-free flour or cornstarch as a thickener if you need a gluten-free option.
Simply add a ¼ cup of heavy cream during the last half the baking to give it a deeper and creamier consistency.
Variations
- Italian Twist: For a variation, add 2 cloves minced garlic to 1 tablespoon olive oil and sauté before making the sauce for an Italian-inspired flavor. Incorporate 2 teaspoons of Italian seasoning and 1 teaspoon of garlic powder into the sauce mixture for extra zest. This family favorite, with its beef bouillon-infused broth, is perfect for a quick and flavorful weeknight dinner.
- Meat: Use 1lb ground beef if you don’t have leftover roast beef, and be sure to add some seasoning while browning the meat before adding to the casserole. Or use leftover cubed rotisserie chicken.
- Cheese: Use cheddar cheese, Monterey Jack, or your favorite cheese blend instead of just mozzarella.
- Noodles: Use egg noodles or a differently shaped pasta such as shells or bowtie.
- Veggies: Add sliced zucchini, chopped broccoli, or diced bell peppers.
- Sauce: Use a different style of condensed soup, such as cheddar soup or cream of onion soup, to lend a different flavor to the dish.
- Seasonings: Season with your favorite herbs like rosemary, basil, or oregano.
- Topping: To add a crunch to your topping, mix 1 cup of crushed buttery crackers or seasoned breadcrumbs with the cheese before baking.
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I used the leftovers from our Sunday roast and it turned into a completely different, delicious dinner. The noodles soak up all that savory beef flavor, and the topping adds the perfect crunch.
Yes, this recipe is perfect for leftover roast. Very pleased it turned out well, and thank you for the 5 stars!