This soup is like a hug in a bowl.
Creamy mashed potatoes, sharp cheddar cheese, buttery croutons on top — it’s cozy, comforting, and comes together with simple ingredients you probably already have.
It’s one of those recipes I go back to again and again, especially when the weather turns chilly or when I just want something warm and cheesy.
It’s also great for using up leftover mashed potatoes, but I’ll show you how to make it from scratch if you need to.
Why I Love This Recipe
This soup takes me straight back to cozy weeknights at home. It tastes like loaded mashed potatoes, but in soup form — creamy, cheesy, and extra satisfying. Plus:
- It’s made from pantry staples
- It uses up leftover mashed potatoes or potatoes that are starting to sprout
- Comes together in under 30 minutes
- You can easily double it for a crowd
- Feels fancy but is super simple
What You’ll Need
- 4 medium russet potatoes, peeled and chopped
- 3 tablespoons unsalted butter
- 1 small yellow onion, diced
- 3 cloves garlic, minced
- 3 cups low-sodium chicken broth
- 1 cup whole milk
- 1 cup shredded sharp cheddar cheese
- ½ cup sour cream
- Salt and black pepper to taste
- 1 tablespoon olive oil (for croutons)
- 2 cups cubed crusty bread (like baguette or sourdough)
- 1 tablespoon butter (for croutons)
- Chopped chives (optional, for garnish)
Pro Tips
- Dice your potatoes small so they cook faster and blend smoother.
- Use sharp cheddar for bold flavor — mild gets lost in the soup.
- Add croutons right before serving so they stay crunchy.
- Use a potato masher for a rustic texture, or a blender for silky-smooth soup.
- Make a double batch of croutons — they’re addictive!
Tools You’ll Need
- Large soup pot
- Medium skillet
- Cutting board and knife
- Potato masher or immersion blender
- Wooden spoon
- Measuring cups and spoons
Substitutions and Variations
- Use leftover mashed potatoes instead of raw — just skip the boiling step
- Swap cheddar for Gruyère or Monterey Jack
- Sub Greek yogurt for sour cream
- Make it vegetarian with veggie broth
- Add cooked bacon for a loaded version
Make Ahead Tips
- Make the soup base 1–2 days in advance and store in the fridge
- Croutons can be made a day ahead and stored in an airtight container
- Reheat soup gently on the stove, adding a splash of milk if it thickens too much
Servings and Time
Makes: 4 servings
Cook Time: 30 minutes
Mashed Potato Soup with Cheddar and Croutons Recipe
Step 1: Boil the Potatoes
Add 4 peeled and chopped russet potatoes to a large pot. Cover with water and add a generous pinch of salt. Bring to a boil, then simmer for 12–15 minutes until fork-tender.
Step 2: Make the Croutons
While the potatoes cook, heat 1 tablespoon olive oil and 1 tablespoon butter in a skillet over medium heat. Add 2 cups cubed crusty bread and toss to coat. Cook for 5–7 minutes, stirring often, until golden and crisp. Remove from heat.
Step 3: Sauté Onion and Garlic
Drain the potatoes and set aside. In the same pot, melt 3 tablespoons butter over medium heat. Add 1 diced small yellow onion and cook 5 minutes until soft. Stir in 3 cloves minced garlic and cook 1 more minute.
Step 4: Add Broth and Potatoes
Pour in 3 cups chicken broth and add the drained cooked potatoes back to the pot. Stir and bring to a low simmer.
Step 5: Mash the Potatoes
Use a potato masher to mash the potatoes directly in the broth until mostly smooth with some small chunks for texture.
Step 6: Stir in Dairy and Cheese
Reduce heat to low. Stir in 1 cup whole milk, 1 cup shredded sharp cheddar cheese, and ½ cup sour cream. Stir until smooth and creamy. Season with salt and pepper to taste.
Step 7: Serve and Top
Ladle soup into bowls. Top with crispy croutons, more cheddar if you like, and chopped chives.
Macros (Per Serving — Approximate)
- Calories: 420
- Protein: 12g
- Carbs: 43g
- Fat: 23g
- Fiber: 3g
- Sugar: 5g
Why This Recipe Works (Quick Science)
Mashed potatoes act as a natural thickener. When blended with broth and dairy, their starches break down and give the soup a rich, velvety texture without needing flour. Melting cheddar into the hot soup creates a smooth, creamy mouthfeel thanks to the proteins in the cheese emulsifying with the fat and starches.
Common Mistakes
- Not seasoning enough: Potatoes need salt to shine. Taste as you go.
- Adding cheese over high heat: This can make it grainy. Keep the heat low when stirring in cheese.
- Using watery bread for croutons: Choose dense, crusty bread for the best crunch.
- Skipping the mash: Don’t skip mashing or blending, or the texture won’t be right.
What to Serve With
- A crisp green salad with vinaigrette
- Roasted broccoli or carrots
- Ham or rotisserie chicken on the side
- A warm baguette for dipping
FAQ
Can I use leftover mashed potatoes?
Yes! Use about 3–4 cups and skip boiling the potatoes.
Can I freeze this soup?
It’s best fresh, but you can freeze it. Reheat slowly and add milk to bring it back to life.
Can I use other cheeses?
Totally — Gruyère, Monterey Jack, or a smoked cheese work great.
How do I make it vegetarian?
Swap the chicken broth for veggie broth.
What if I don’t have sour cream?
Use Greek yogurt or a splash of heavy cream.