Mashed Potato Soup

Have leftover mashed potatoes? Repurpose them and make a pot of cozy and delicious Mashed Potato Soup! Ready under 15 minutes – leftover mashed potatoes is a shortcut to an amazing potato soup – so never toss them if you have extra!

Our leftover mashed potato soup recipe is thick and creamy, loaded with bacon, sour cream and cheddar cheese. It is truly a yummy and comforting meal for a cold day.

Cozy soups are our gem! If you love this, also check out Ravioli Soup, Leftover Turkey Stew and Beef Noodle Soup – they are also so delicious!

Leftover Mashed Potato Soup

After a big holiday meal, the last thing I want is to eat the same leftovers over and over again. That’s why it’s so helpful to be able to repurpose them…like making potato soup from mashed potatoes!

If you have leftover mashed potatoes from Christmas, Thanksgiving, or Easter dinner, DO NOT toss them, but instead transform them into this thick, hearty and creamy leftover mashed potato soup!

This mashed potato soup is very similar to our Creamy Potato Bacon Soup, except that instead of using raw potatoes, we are using mashed potatoes. But I’m telling you, it’s so good, you will forget it came from leftovers!

Making potato soup with mashed potatoes is SUCH a good idea because mashed potatoes are typically made with potatoes and lots of dairy, which is usually milk, heavy cream, or cream cheese. That’s exactly what gives potato soup that rich, silky and creamy texture.

In my humble opinion, no mashed potato soup is complete without some bacon and cheese – two ingredients that complement potatoes so dang well it’s hard to eat one without the other! So of course we have to bring that into our recipe.

Our mashed potato soup promises lots of amazing flavors (thank you, bacon + bacon grease!), ultra creaminess, and lots of coziness.

So, don’t eat those leftover mashed potatoes over and over again after the holidays…make a pot of potato soup using mashed potatoes instead! Trust me, it’s worth that extra 15 minutes!

Ingredients

Here are the ingredients you will need to make mashed potato soup!

• Mashed potatoes: Well, duh! 😉 Making potato soup with mashed potatoes is a quick, easy, and delicious way to use them up without wasting them.
• Butter: Salted butter is what this recipe calls for. If you only have unsalted butter, that works too – just add a pinch more salt at the end.
• All-purpose flour: Flour gives the soup a thicker consistency. Nothing better than a thick and creamy soup!
• Milk: Using 2% or higher is ideal for a creamy potato soup. If you would like a bit more richness to the soup, you can substitute half of the milk with either half and half or heavy cream.
• Chicken broth: There are so many options at the grocery store. I find that ‘free range’ chicken broth has the best flavor.
• Bacon bits: To make this recipe quick and simple, use bacon bits. High quality bacon bits work as well as raw bacon to season the soup. If not, raw bacon can be used, you’ll just have the extra step of cooking it.
• Sour cream: It really helps to round out the flavor of this soup.
• Cheddar cheese: What is potato soup without cheese?! You can choose your preferred cheddar whether it be mild, medium, or sharp.
• Kosher salt and black pepper: For seasoning at the end. Taste first, since your mashed potatoes and broth may already be salty.

how to make potato soup with mashed potatoes

It’s so easy to use leftover mashed potatoes to make potato soup. It takes less than 15 minutes to make this cozy soup and it tastes so good you won’t believe you are repurposing leftovers!

No peeling potatoes; only one pot is needed; you don’t even have to cook the bacon separately if you don’t want to!

Step 1: Make the roux and add the broth

First, in a large pot, melt butter and add all purpose flour.

Whisk the butter and flour mixture for a minute under low heat, kinda like making a roux.

Once combined, add chicken broth and milk. Stir as you bring it to a boil.

Step 2: Add the leftover mashed potatoes

Once it comes to a boil, add mashed potatoes, sour cream and bacon bits.

Using bacon bits saves a whole lot of time, as compared to using raw bacon. These days you can find high quality bacon bits that tastes just as good as real bacon especially when we are just flavoring our mashed potato soup with it.

If using raw bacon strips instead of cooked bacon bits, cook the bacon strips in the oven or on stovetop. If cooking in the oven, line a baking sheet with aluminum foil. Place bacon strips on pan without overlapping. Bake for 15 min. Chop bacon into small bits.

Step 3: simmer until thick and creamy

Stir and bring to a boil. Lower to medium-low heat and let your mashed potato soup simmer until it thickens to your desired consistency.

Add shredded cheddar cheese and mix until melted.

Step 4: Season and serve

Taste the soup and add kosher salt and black pepper as needed. Because some mashed potatoes or the broth are already salty, you may not need to add salt.

When you make potato soup using mashed potatoes, there could be a bunch of variations of flavor in the mashed potatoes themselves, so be sure to taste at the end and make adjustments as you see fit.

Optional: you can garnish mashed potato soup with bacon, green onions, chives and/or a sprinkle of shredded cheese.

Last but not least, enjoy this cozy bowl of deliciousness!

Variations and Substitutions

There is a wide variety of mashed potatoes – some are creamier, some are drier, some use starchier potatoes etc. You’ll need to adjust accordingly. Taste your soup at the end and make changes as necessary:

• Creamier soup: Add more milk or cheese.
• Tangier bite: Add an extra dollop right before serving.
• Thicker soup: Simmer a little longer until it reaches the consistency you like.
• Thinner soup: Add a splash more broth at a time to thin it out.
• Salty soup: Reduce the bacon and/or cheese, or leave out the added salt.
• Unsalted butter: Perfectly fine in place of salted butter. Just add an extra pinch of salt at the end after tasting.
• Vegetable stock: Swap it in for the chicken broth for a lighter, milder taste.
• Sour cream substitute: Plain Greek yogurt adds a similar tang. Mix it in at the very end, off the heat, so it doesn’t curdle.
• Different cheese: Mild, medium, or sharp cheddar all work well. Monterey Jack or pepper jack are tasty swaps too.
• Other mashed potatoes: Garlic, cheesy or loaded mashed potatoes all work here. Our Cheesy Mashed Potatoes are another good option. Just taste before adding extra salt or cheese.
• Leftover ham: Diced ham makes a smoky addition that pairs well with the cheese.

make ahead, storage, and reheating

Make ahead: This soup is a great one to make a day ahead. It thickens as it sits, so you may need a splash of milk or broth when you reheat it.

Refrigerator: Store mashed potato soup in an airtight container in the refrigerator for up to 5 days.

Freezer: Freezing is fine but know that it will change the texture of the soup slightly after the soup defrosts. The soup will be grainy in texture because of the dairy content.

Reheating: For best results, thaw frozen soup overnight in the refrigerator first. Reheat gently on the stovetop over medium-low heat, adding a splash of milk or broth if it has thickened too much. The microwave works too, in 30-second bursts.

How To Serve Mashed Potato Soup

Ladle the soup into warm bowls and sprinkle with extra shredded cheddar and chopped chives or green onions. For some crunch, top each bowl with a handful of Homemade Croutons.

Crusty bread is great for dunking, or try our Cheese Stuffed Dinner Rolls for a heartier side.

Want to go all out? Serve the soup in hollowed-out bread bowls for a fun, cozy presentation. A simple green salad on the side balances out the rich, creamy soup.

Tips And Tricks

Here are a few simple tips to help you get a creamy, smooth pot of soup:

• Taste before you season: Leftover mashed potatoes, broth and any salty toppings can all bring their own salt, so taste first and add kosher salt and black pepper at the end.
• Warm up cold potatoes: Cold mashed potatoes are stiff and can clump. Break them up with a whisk or potato masher as they heat in the broth.
• Don’t walk away from the roux: The butter and flour mixture can scorch quickly, so keep it moving and add the broth and milk as soon as it’s combined.
• Use a heavy-bottomed pot: It spreads the heat evenly and helps keep a dairy-based soup from sticking to the bottom.
• Keep the heat gentle: After the soup comes to a boil, lower the heat so the dairy doesn’t separate.
• Thicken with a quick slurry: If the soup is still thinner than you like after simmering longer, whisk 1 to 2 tablespoons of flour into a few tablespoons of cold milk, add it to the pot, and simmer for a few minutes until thickened.
• Blend for a smoother soup: Prefer a silky texture? Give the soup a few pulses with an immersion blender, leaving some chunks if you like.
• Shred your own cheese: Pre-shredded cheese is often coated with anti-caking agents that can keep it from melting as smoothly.
• Add toppings at the end: Chives, green onions, and extra cheese stay fresh and bright when they go on each bowl right before serving.

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More Holiday Leftover Recipes

• For leftover turkey: Turkey Stew, Turkey Salad with Cranberries
• For leftover cranberry sauce: Cranberry Baked Brie
• For leftover ham: Ham and Cheese Crescent Roll Ups, Easy Frittata with Ham, Asparagus and Ham Quiche