Incredibly Tasty Leftover Prime Rib Beef Barley Soup With Mushrooms (2024)

This leftover prime rib beef barley soup with mushrooms will leave you planning to make a lot more prime rib roast in the very near future! Save any rib bones for the best-ever prime rib soup bone broth that will make this soup even more amazing! It's hearty, delicious, and incredibly satisfying!

Upgrade Your Beef & Barley Soup

My prime rib beef and barley soup is loaded with fantastic flavors and a wonderful assortment of complimentary vegetables; all made even better with tender leftover pieces from your prime rib roast holiday dinner!

Over the years, I have always prepared plenty of prime rib during the holidays, and I enjoy making the usual leftover meals afterward.

However, I knew that with such an amazing roast (even if you use the less costly cross-cut portion or are preparing a standard roast beef or baron of beef) I really should be striving for some pretty phenomenal meals and recipes to create from those prime portions of perfectly roasted prime rib beef.

🥘 Ingredients

Don't let the ingredients make you think twice about making this soup! It's an amazing soup that really deserves a few extra ingredients!

• Olive Oil - 1 tablespoon of extra virgin olive oil.
• Onion - 1 small yellow or white onion, diced. These are rich, flavorful, and aromatic which is what makes it such a good base for so many soups, sauces, and more!
• Garlic - 1 tablespoon of minced garlic.
• Rosemary - 1 sprig of rosemary. Another herb that makes great soups, and pairs well with beef and hearty proteins (or use a rosemary substitute).
• Bay Leaves - Use at least 3 leaves, up to 4, depending on their size (or use a substitute for bay leaves).
• Basil - ½ tablespoon of fresh, chopped basil.
• Butter - 2 tablespoons of butter. Use European butter for extra richness.
• Carrots - 4 small to medium-sized carrots, chopped.
• Parsnips - 2 small to medium-sized parsnips, chopped.
• Leek - 1 leek, cleaned and chopped.
• Celery - Three ribs of celery are part of the mirepoix or 'holy trinity' of vegetables used as soup and cooking bases - along with carrots and onion.
• Tomatoes - Two small tomatoes, chopped.
• Mushrooms - 8 ounces of mushrooms, rinsed and quartered. You can use buttons, bellas, crimini, or a combination of them.
• Tomato Paste - ⅓ cup of tomato paste. Builds that amazing tomato flavor in the soup base.
• Horseradish - ½ tablespoon of grated horseradish is added to this soup; hopefully, you have some in the refrigerator after serving my creamy horseradish sauce with your prime rib!
• Salt & Pepper - Adjust to taste.
• Red Wine - 1 cup of red wine. I used Malbec, but you can use any full-bodied red wine.
• Beef Broth - 9 cups of beef broth. Two portions, 6 cups, and 3 cups.
• Quick Barley - 1 cup of either quick or pearled barley.
• Prime Rib - 1 pound of leftover prime rib roast, chopped into 1" bite-sized cubes or strips.
• Red Wine Vinegar - ½ tablespoon of red wine vinegar.

*Be sure to see the free printable recipe card below for ingredients, exact amounts & instructions with tips!*

🔪 How To Make Leftover Prime Rib Beef Barley Soup

There may be a few steps involved, but this prime rib soup is easily the very best soup you could use your roast leftovers in. All you need is a large stock pot, a cutting board, a knife, a saucepan, a wooden spoon, and your measuring utensils.

This recipe will make a hearty 8 portions of soup.

Make the Soup Base

1. Heat and saute. Bring a large stock pot with 1 tablespoon (15 milliliters) of olive oil to medium-high heat. The oil should be shimmering when ready to sauté the onion and garlic. Add 1 onion, 1 tablespoon (15 grams) of garlic, 1 rosemary sprig(s), 3 bay leaves, and ½ tablespoon (7 grams) of basil then saute for 2-4 minutes until the onion and garlic are tender, no longer translucent, and fragrant.
2. Add vegetables. Melt 2 tablespoons (30 grams) of butter with the sauteed onion and garlic, then add the remaining vegetables, including 4 carrots, 3 ribs of celery, 2 parsnips, 1 leek, 2 tomatoes, and 8 ounces (227 grams) of mushrooms. Cook for 8-10 minutes, stirring occasionally.
3. Stir in tomato paste and horseradish. After cooking, and the vegetables have softened, stir in ⅓ cup (87 grams) of tomato paste and ½ tablespoon (7 grams) of grated horseradish, then season with salt and pepper. Keep stirring the vegetables, tomato paste, and horseradish until the paste is evenly distributed throughout. The color of the tomato paste will also start darkening to a deep red color after about 3 minutes.
4. Deglaze the pan. Stir in 1 cup (240 milliliters) of red wine, scraping the bottom of the soup pot to remove any stuck pieces. Continue cooking for about 3 minutes while the wine simmers off, reducing the wine by about half. *You can use more broth for this step for an alcohol-free alternative.

Add Prime Rib Leftovers

1. Prime rib and broth. Add the cut portions of 1 pound (454 grams) of leftover prime rib (or roast beef, pot roast, or leftover steak) along with the first 6-cup (1440 milliliters) portion of beef broth. Stir, cover, reduce the heat to low, and simmer for about 70-75 minutes.
2. Wait to start the barley. Start cooking your barley (below) after about 45 minutes of simmering the soup.

How To Cook Barley For Soup

1. Bring barley to a low boil. In a saucepan, bring the second portion of beef broth (3 cups / 720 milliliters) to a boil. Add 1 cup (184 grams) of barley and cook at a low boil over medium heat until al denté, or about 20 minutes.
2. Transfer the barley. The liquid will not be absorbed completely; do not drain off excess broth. Add the broth and cooked barley to your soup.

Simmer & Serve

1. Simmer and season. Finish cooking at a simmer after the barley and broth have been combined with the soup ingredients. The barley will be tender when cooked completely, about 10-12 minutes. *This is a great time to taste and adjust seasoning.
2. Add a splash of red wine vinegar and serve. Remove the soup from heat when done, add ½ tablespoon (7 milliliters) of red wine vinegar, then serve immediately.

🥗 Sides

Garnish with more basil or fresh, chopped parsley if desired. Serve your soup on its own or pair it with a light garden salad and some butter herb Rhodes rolls. You can even serve it in a homemade bread bowl! Enjoy!

💭 Tips & Notes

• If you don't have any prime rib leftovers, you could cook some (try my grilled prime rib, oven-roasted prime rib, or smoked prime rib). On the other hand, you could also make this amazing soup using ground beef, some leftover steak, leftover pot roast, or even leftover brisket!
• If avoiding alcohol, you can substitute the red wine for an additional cup of beef broth.
• I highly recommend using the bones from your prime rib to make an incredibly delicious bone broth for this soup! If not, you can always use the storebought kind!

🥡 Storing & Reheating

Leftover prime rib beef barley soup stores and freezes exceptionally well! As a matter of fact, the flavor has combined for an even more satisfying soup after a day or two!

Refrigerate any leftover prime rib soup in an airtight container. Your barley soup will last for up to 3-4 days when stored properly.

Freezing

Freeze your soup by storing it in an airtight freezer container. Frozen beef barley soup is good for up to 3 months.

Thaw any frozen soup in the refrigerator overnight before reheating. *I do not suggest re-freezing the soup once it is thawed or reheated.

Reheating

The best way to reheat beef barley soup is on the stovetop. Place your desired portion into a saucepan and heat over medium-low until warmed.

Of course, the fastest way to reheat your soup is in the microwave. Portion your soup out into a microwave-safe bowl and heat for 1-2 minutes; stir and continue heating in 30-second increments until fully heated.

🥩 What To Make With Leftover Prime Rib

Enjoy some of my other fantastic leftover prime rib recipes, including the wildly popular recipes for Leftover Prime Rib Beef Stroganoff or the post-Christmas breakfast dish, Leftover Prime Rib Hash, and my easy-to-make Prime Rib Pasta or Leftover Prime Rib Tostadas. I'm always adding more, so be sure to check in!

>>>>See all of my recipes here<<<<

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