Easy Mashed Potato Soup
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After Thanksgiving last year, I found myself with an abundance of leftover mashed potatoes. As I looked at the delicious leftovers, I thought about creative ways to use them up instead of letting them go to waste. That’s when the idea struck—why not transform them into a comforting, hearty soup? The thought of turning those creamy mashed potatoes into an easy, flavorful dish felt like the perfect solution. The result was this recipe for easy mashed potato soup.
This soup is a quick and satisfying way to repurpose leftovers into something entirely new. With just a few additional ingredients, those leftover potatoes became a rich, creamy soup that warmed us up on a chilly evening. It was so simple to make and flavorful, making it the ultimate comfort food. Whether you’re looking to reduce food waste or just want to enjoy something cozy, this soup is a must-try!

If you don’t typically find yourself with leftover mashed potatoes but still want to try this delicious soup, it’s easy to plan ahead. The next time you’re making mashed potatoes for dinner, simply whip up a little extra and set them aside. This way, you’ll have the perfect base ready for turning into a creamy, comforting soup without any extra effort. It’s a great excuse to indulge in mashed potatoes now and enjoy them again in a whole new way!
And let’s not forget about the garnishes. The finishing touch is what takes this soup from good to truly spectacular. Top your bowl with crispy bacon bits, shredded cheddar cheese, a dollop of sour cream, or a sprinkle of chives. They add a burst of color and flavor. These simple additions enhance the taste and make the soup feel extra special. Whether you’re serving it to guests or enjoying it solo, those garnishes add that final flair that everyone loves!
Ingredients for Easy LEFTOVER Mashed Potato Soup
- BUTTER
- ALL-PURPOSE FLOUR
- SALT
- BLACK PEPPER
- CHICKEN BROTH
- WHOLE MILK OR HALF AND HALF
- MASHED POTATOES
- CHEDDAR CHEESE
- TOPPINGS – CHEESE, BACON BITS, GREEN ONION/CHIVES, SOUR CREAM

Instructions for Easy Mashed Potato Soup RECIPE
Start by melting the butter in a large pot over medium heat. Once melted, add the flour, salt, and pepper to the pot. Use a whisk to combine everything to create a roux. Cook the mixture for about 1 minute to remove any raw flour taste.
Gradually pour the chicken broth into the pot while whisking constantly to ensure a smooth, lump-free base. After the broth is incorporated, stir in the milk, mashed potatoes, and shredded cheddar cheese. Cook the soup for about 5 minutes, stirring frequently. You want to prevent the cheese from sticking to the bottom of the pot and burning. Heat the soup just until it begins to simmer.
Allow the soup to simmer until it reaches your desired thickness, stirring occasionally. Once ready, ladle the soup into bowls and serve immediately. Don’t forget the toppings! Garnish with crispy bacon, shredded cheese, sour cream, or chopped chives to add a burst of flavor and a colorful finish to this comforting dish.

Frequently Asked Questions
Can I use instant mashed potatoes for this soup?
Yes, you can use instant mashed potatoes if you don’t have homemade leftovers. Prepare them according to the package instructions, then use them as you would in the recipe. Keep in mind that the flavor and texture will vary slightly.
How do I store leftovers?
Allow the soup to cool completely before transferring it to an airtight container. Store in the refrigerator for up to 3 days. Reheat gently on the stovetop or in the microwave, stirring occasionally to ensure even heating.
Can I freeze this soup?
It’s best not to freeze this soup as the dairy (milk and cheese) may separate and create a grainy texture when reheated. For the best results, enjoy the soup fresh or refrigerate leftovers to use within a few days.
Can I adjust the consistency of the soup?
Yes, you can easily adjust the thickness. If the soup is too thick, add more milk or broth a little at a time until it reaches your desired consistency. If it’s too thin, let it simmer a bit longer to thicken or add more mashed potatoes.
Can I add other ingredients to the soup?
Definitely! This recipe is versatile. You can add cooked diced ham, roasted garlic, or even steamed veggies like broccoli or cauliflower to give it a unique twist.

Easy Mashed Potato Soup
Real Mom Kitchen
Equipment
Ingredients
- 2 Tbsp butter
- 2 Tbsp flour
- ½ tsp salt
- ¼ tsp ground pepper
- 4 cups chicken broth
- 1 cup whole milk
- 4 cups prepared mashed potatoes
- ½ cup cheddar
- optional toppings Cheddar cheese, bacon, green onion/chives, sour cream
Instructions
- Melt butter in a large pot over medium heat. Add flour, salt, and pepper, whisking until smooth. Cook for 1 minute.
- Gradually whisk in chicken broth, ensuring a lump-free mixture.
- Stir in milk, mashed potatoes, and cheddar cheese. Cook for about 5 minutes, stirring constantly to prevent burning, until the soup reaches a simmer.
- Continue cooking, stirring occasionally, until the soup thickens to your desired consistency.
- Serve hot with optional toppings like crispy bacon, shredded cheese, sour cream, or chives.
Nutrition
This recipe is adapted from Wholefully.