The butter and onion soften together first, and the kitchen starts to smell savory before the potatoes even hit the pot. As the cubes simmer, the broth thickens and the edges of the potatoes begin to soften, but the soup still needs a little help to get that creamy, chunky texture. That’s where this cheesy potato soup takes a useful middle path: it’s rich without turning into a bowl of mashed potatoes.
I like how the sharp cheddar and sour cream finish the soup after the pot comes off the heat. The cheese melts into the warm broth, while sour cream brings a gentle tang that keeps each spoonful from feeling too heavy. The potatoes stay in visible pieces, with just enough mashed against the side of the pot to make the base thick and comforting. A bowl is best served warm, while the cheddar is still silky.

Kitchen Note
Keep the potato pieces close to a half-inch so they soften at roughly the same pace. Oversized cubes can still feel firm when the smaller pieces are ready to mash.
Save this cheesy potato soup for a cozy dinner: sharp cheddar, tender russets, and a creamy broth with plenty of potato chunks.
Why This Soup Needs Both a Roux and a Few Mashed Potatoes
A creamy potato soup can end up thin if the broth and milk are doing all the work, or pasty if every potato is mashed into the base. Here, the flour stirred into the butter and softened onion thickens the liquid throughout the pot. Russet potatoes add their own starch as they cook, so the soup builds body without needing a separate thickener at the end.
Mashing only some of the potatoes gives you control over the final texture. The pieces you leave whole make the soup feel hearty, while the mashed portion blends into the broth and gives each spoonful a creamy consistency. If you mash too much, you lose that contrast; if you skip the mashing entirely, the soup will have a looser base. The point isn’t to make every cube disappear. It’s to let a little potato do the thickening while the rest stays in chunks.
What the Potatoes, Dairy, and Cheese Each Bring

- Russet potatoes — Their starchy flesh helps thicken the broth, and they soften enough to mash easily. Choose firm potatoes without soft spots. Yukon Gold potatoes are a workable substitute, but they’re less starchy, so the finished soup will be less thick and a little waxier.
- Sharp cheddar — Sharpness keeps the cheese noticeable against the potatoes and milk. A block of cheddar that you shred at home tends to melt more smoothly than pre-shredded cheese; Monterey Jack can replace it for a milder, softer cheese flavor.
- Whole milk and sour cream — Whole milk gives the broth a fuller body, while sour cream adds tang at the end. Two-percent milk works if that’s what you have, though the soup will be less rich. Plain Greek yogurt can stand in for sour cream; it tastes tangier and may make the soup a touch less creamy.
- All-purpose flour — Flour thickens the broth and milk into a creamy base. For a gluten-free version, replace it one for one with a cup-for-cup gluten-free flour blend; choose one designed to replace wheat flour in cooking, since blends can behave differently.
- Low-sodium chicken broth — A carton is convenient and works well here. Low-sodium broth lets the onion, cheddar, and added kosher salt stay in balance; regular broth can make the finished soup taste saltier.
- Yellow onion and garlic — The onion becomes sweet and tender as it cooks in the butter, and fresh garlic gives the base a fuller aroma. A standard grocery-store onion and garlic are entirely fine; there’s no need to seek out specialty varieties.
- Unsalted butter — It carries the onion and garlic flavors and gives the flour a rich base. Store-brand butter works just as well as a pricier option, and unsalted butter keeps the seasoning easier to control.
Building the Creamy Base Before the Potatoes Go In
Soften the onion in butter
Melt the butter in a 6-quart pot over medium heat. Add the diced onion and cook for 5 to 7 minutes, stirring occasionally, until softened; it should look translucent and tender rather than browned. Stir in the minced garlic and cook for 30 seconds. Keep the heat at medium so the garlic turns fragrant without scorching.
Whisk the broth and milk in gradually
Sprinkle the flour over the onion mixture and stir for 1 minute, coating the onion and butter evenly. Gradually whisk in the chicken broth and milk until the liquid looks smooth. Pouring in the liquid a little at a time gives the flour a chance to disperse; if you see small lumps, keep whisking before adding the potatoes. The base should look creamy and even.
Simmer until the potatoes are fork-tender
Stir in the potatoes, kosher salt, and black pepper, then bring the soup to a gentle boil. Reduce the heat and simmer uncovered for 15 to 20 minutes, stirring occasionally. The potatoes are ready when a fork slides easily into a cube without it falling apart. If they’re still firm, give them more time at a gentle simmer rather than raising the heat sharply.
Mash a little, then finish off the heat
Remove the pot from the heat and press some of the potatoes against the side of the pot to mash them. Leave plenty of chunks so the soup stays hearty instead of turning completely smooth. Stir in the shredded cheddar and sour cream until the cheese melts and the soup looks creamy. Serve warm.
Simple Ways to Adapt This Potato Soup
Make it vegetarian with vegetable broth
Replace the chicken broth with the same amount of low-sodium vegetable broth. The soup keeps its creamy texture, though the base will taste a little less savory and chicken-forward.
Make the texture smoother
Mash more of the cooked potatoes against the side of the pot before adding the cheddar and sour cream. The base will be thicker and more uniform, with fewer distinct potato pieces; keep a few cubes intact if you still want some chunkiness.
Storage and Reheating
- Refrigerator: Store covered for 3 to 4 days. The soup will thicken as it chills, and the potatoes may soften further.
- Freezer: Freezing isn’t ideal. The potatoes can turn mealy and the dairy may separate after thawing, so the soup won’t have the same creamy texture.
- Reheating: Warm it slowly in a saucepan over low heat, stirring often, until it reaches 165°F. Avoid a hard boil, which can cause the dairy to separate.
Questions That Come Up When Making Cheesy Potato Soup

Cheesy Potato Soup
Ingredients
Method
- Melt the butter in a 6-quart pot over medium heat.
- Add the onion and cook for 5 to 7 minutes, stirring occasionally, until softened.
- Stir in the garlic and cook for 30 seconds.
- Sprinkle the flour over the onion mixture and stir for 1 minute.
- Gradually whisk in the chicken broth and milk until smooth.
- Stir in the potatoes, salt, and pepper.
- Bring the soup to a gentle boil, then reduce the heat and simmer uncovered for 15 to 20 minutes, stirring occasionally, until the potatoes are fork-tender.
- Remove the pot from the heat and mash some of the potatoes against the side of the pot to thicken the soup, leaving plenty of chunks.
- Stir in the cheddar and sour cream until the cheese is melted and the soup is creamy.
- Serve warm.



