Leftover Pot Roast Soup adds fresh herbs and meaty mushrooms for a rich, brothy soup that is comfort food at it’s best! And it could not be easier.
Why You’ll Love This Leftover Pot Roast Soup
A cozy second life for yesterday’s pot roast. This recipe transforms leftover pot roast into a rich, comforting soup that tastes completely new—no one will guess it started as leftovers.
Deep, savory flavor in every spoonful. Mushrooms, garlic, thyme, and a splash of red wine (or balsamic!) build a beautifully layered broth that feels slow-simmered, even though it comes together quickly.
Thick, hearty, and satisfying. A simple cornstarch slurry turns the broth velvety without making it heavy, giving the soup that luxurious, stew-like texture your family will love.
Weeknight-easy, cabin-weekend cozy. Everything cooks in one pot, and the simmer time is short—perfect for busy days when you want something homemade and comforting.
Bright, fresh finish. A squeeze of lemon at the end wakes up all the flavors and balances the richness, making each bowl feel extra special.
If there’s a season for soup, Fall is it, though I think soup is great anytime of year. So, as the weather gets colder, the craving for “comfort food” becomes greater. And pot roast is about as comfortable as it gets, especially because you can almost always count on leftovers. This Leftover Pot Roast Soup is one of my favorites because you don’t need a lot of roast in the recipe (only about 2 cups), but the soup is both hearty and satisfying.
Leftover Pot Roast Soup adds fresh herbs and meaty mushrooms for a rich, brothy soup that is comfort food at its best! And it could not be easier. Use fresh or dried thyme, whichever is available, but top with fresh parsley for a nice, bright finish.
If you don’t have the leftover pot roast YET, why not try this foolproof Chuck Roast In Foil recipe with instant side dishes and easy cleanup. And IF you have any leftover roast afterward, well I have something for you right here…
If you’re looking for a good bread idea for dipping in the soup, I have just the recipe for that too. Incredible Cheese Bombs really are “incredible”. Enjoy.
Serving Suggestions
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Warm crusty bread or buttered baguette slices are perfect for dunking into the creamy broth.
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Add a simple green salad with lemon vinaigrette for a fresh counterpoint to the hearty soup.
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Serve over mashed potatoes or buttered egg noodles to turn it into a full comfort-style meal.
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Garnish with extra parsley, a swirl of heavy cream, or even a spoonful of horseradish for a fun flavor twist.
FAQ
Can I make this soup with fresh beef instead of leftover pot roast?
Yes! Brown bite-size pieces of beef chuck in the pot before adding the onions and mushrooms, then simmer an extra 20–30 minutes until tender.
What if I don’t have mushrooms?
You can leave them out or replace them with diced carrots or celery for added texture.
Can this soup be frozen?
Absolutely. The texture holds up well—just thaw overnight and reheat gently on the stove.
Can I make this gluten-free?
It already is! Cornstarch thickens the soup without any flour.
How can I lighten this soup?
Use low-sodium broth and add extra vegetables like zucchini, carrots, or kale.
Whether you’re stretching a Sunday pot roast or rescuing leftovers from the back of the fridge, this cozy Pot Roast Soup proves that a simple, humble beginning can turn into something truly delicious. It’s the kind of recipe that warms the kitchen, brings everyone to the table, and tastes even better than you expect. I hope it becomes one of those comforting, go-to soups you come back to all winter long. Thanks for stopping by, and enjoy every spoonful!
Leftover Pot Roast Soup
Ingredients
- ⅓ cup cornstarch
- 4 cups beef broth divided
- 3 Tbsp butter
- 1 small onion chopped
- 8 ounces baby portobello mushrooms sliced
- 3 cloves garlic finely minced
- 2 Tbsp fresh thyme chopped (or 2 teaspoons dried thyme)
- ¼ cup red wine or 2 Tablespoons balsamic vinegar
- Approximately 2 cups pot roast cooked and shredded
- 1 Tbsp parsley chopped
- Lemon wedges optional
Instructions
- In a small bowl, combine ⅓ cornstarch with 1 cup of the beef broth. Whisk and let sit.⅓ cup cornstarch, 4 cups beef broth
- In a large sauce or stock pan, melt 3 Tablespoons butter over medium heat. Add 1 chopped onion and 8 ounces mushrooms and cook until the mushrooms have released their moisture and it has evaporated, about 12-15 minutes.3 Tbsp butter, 1 small onion, 8 ounces baby portobello mushrooms
- Add 3 cloves garlic and 2 Tablespoons thyme and cook until fragrant, about 1 minute.3 cloves garlic, 2 Tbsp fresh thyme
- Add ¼ cup wine and cook until it is absorbed.¼ cup red wine
- Add the cornstarch mixture and remaining 3 cups of beef broth and the beef. Bring to a boil, reduce the heat and simmer for 15 minutes.
- Mix in 1 Tablespoon parsley and remove from heat. Let sit 5 minutes and soup will continue to thicken.1 Tbsp parsley
- Give a final stir and serve. Squeeze lemon wedges over finished soup also, if desired.Lemon wedges
Notes
- Leftover pot roast shines here. Fatty or lean cuts both work well, and the soup actually tastes better as it sits.
- Mushrooms matter. Baby portobellos add deeper flavor, but any variety—even a mix—works beautifully.
- Cornstarch thickens as it cools. If the soup seems thin at first, give it the full resting time before adjusting.
- No wine? No problem. Balsamic vinegar adds the same depth and brightness.
Love this soup and it’s a great way to use leftover pot roast. The only thing I did differently was to add the leftover gravy. My gravy is really good and it really adds to the soup!
Hi Peg, this is a great idea! Thanks for taking the time to comment. It means a lot!
Very good! I used 1/3C corn starch and it was a bit too thick, just added a bit more water and it came together wonderfully. Great leftover recipe. Thanks!
Thanks for making the soup Maria! I’m glad it worked for you even if you needed to thin it out a bit. I’ll be making a slow cooker pot roast this week so thanks for reminding me about this recipe for a good one with leftovers. I haven’t made it in awhile.
This is great soup! I was looking for something to do with leftover pot roast. Yes, it almost got a little bit too thick, but I caught it in time and added a little more wine and all was well. Definitely a keeper!
Soup was way too thick. Mine looked much thicker than picture but i only used exactly 1/2 cup cornstarch. Maybe it sat too long before i added or i cooked it too high???
It was like a real thick gravey. Next time i think i will use 1/4 cup cornstarch
Hi Debbie, I’ve never had mine get too thick so sorry about that. I’ll add a note into the printable recipe to add between 1/4 and 1/2 cup cornstarch. Thanks for this info.
Will this freeze well?
Hi Sarah, this is a fine soup for the freezer. Thanks for stopping by!
When do you add the roast beef? I would imagine at the end?
Step 5
Hi Elizabeth, I’m not sure what you’re asking?