Leftover mashed potato soup is for my pal, Lisa, who loves potato soup. I had a very old recipe on my blog for baked potato soup that I made for her, but in my re-launch, I lost it. I decided to create a new recipe using leftover mashed potatoes. Using leftover mashed potatoes means you don’t have to wait for potatoes to cook so this is a fast recipe; you can have it on the table in less than 30 minutes.
It took a few tries to get this recipe right; the key was the ratio of mashed potatoes to chicken stock. A ratio of 1:1 (by volume) works perfectly and creates a just-thick-enough soup. To guarantee the right texture, I also added just a touch of flour to my mirepoix; this teeny bit of roux was a perfect addition.
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And, let’s be honest, baked potato soup is all about the toppings. I like bacon, scallions, sour cream, and cheese. But use your imagination and make your bowl your own. I think next time I might add some crunchy French fried onions. Yum!
This is the easiest way to make baked potato soup. And, it’s a very tasty and comforting way to use leftovers in the fridge. Bookmark this recipe for the holiday aftermath when you’re guaranteed to have a stash of leftover mashed potatoes.
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Leftover Mashed Potato Soup | The Easiest Baked Potato Soup Recipe
- 2 slices bacon raw
- ½ cup onion diced small, ~¼-inch
- ½ cup carrots diced small, ~¼-inch
- ½ cup celery diced small, ~¼-inch
- 1 tsp flour
- 1 tsp dried thyme
- 1 tsp granulated garlic
- 2 cups chicken stock
- 2 cups leftover mashed potatoes
- salt & pepper, to taste
- toppings: grated Jack cheese, sliced scallions, sour cream or whatever you like!
- Heat a medium soup pot over medium heat. Add the bacon and cook until the bacon has rendered most of it's fat and it's crispy. Remove from the pot and drain on paper towels.
- Add the carrot, onion, and celery to the pot with a large pinch of salt. Cook this mixture for about 5 minutes until the vegetables start to soften. Sprinkle the flour over the vegetables and cook for about a minute while stirring constantly.
- Add the dried thyme, granulated garlic, and chicken stock. Stir to combine well. Bring to a boil and then reduce to a simmer. Cover and let simmer for 10 minutes to soften the vegetables.
- Add the leftover mashed potatoes. Stir well until the potatoes are evenly dispersed into the soup. Bring back to a simmer and cook for about 5 minutes longer to warm up the potatoes and incorporate them into the soup.
- Give your soup a taste and add salt and pepper as needed.
- To serve, ladle into bowls. Top with crumbed bacon, grated cheese, sour cream, and sliced scallions–or the creative toppings of your choice.
- Note about serving size: this recipe makes about 4, 1-cup servings which is good if you’re serving with something else (a salad or sandwich or as the first course of a meal.) If you are serving this as a main course, it will serve two. But it’s easy enough to double!
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