Crockpot Mushroom and Potato Soup

Prep Time	Cook Time	Total Time
20 min	6 h	6 h 20 min

Introduction

This cozy crockpot mushroom and potato soup is creamy, comforting, and packed with tender veggies in every bite.

It slow-cooks all day, so the baby bella mushrooms, potatoes, and carrots turn rich, savory, and full of flavor.

Serve it on a chilly weeknight, for an easy meatless dinner, or as a make-ahead soup for busy days.

Prep mode (keeps screen active)

Prep the vegetables

Peel the onion, potatoes, and carrots, then dice the potatoes and onion and chop the carrots.
Slice the baby bella mushrooms into even pieces so they cook at the same speed.
Sauté the aromatics

Heat the olive oil or butter in a skillet over medium heat.
Add the diced onion and cook until it softens and turns translucent, about 4 to 5 minutes.
Stir in the garlic, carrots, and mushrooms and cook until the mushrooms release moisture and shrink slightly.

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Load the slow cooker

Transfer the sautéed vegetables to the slow cooker insert.
Add the diced potatoes, dried thyme, dried rosemary, salt, black pepper, vegetable bouillon cube, and vegetable broth.
Stir gently to combine everything so the seasonings spread evenly.
Slow cook the soup

Cover the slow cooker and cook on low for 6 to 8 hours or on high for 3 to 4 hours.
Check that the potatoes and carrots are very tender and a fork slides in easily.
Thicken and add the cream

In a small bowl, whisk the heavy cream with the flour until the mixture is smooth with no lumps.
Stir the cream mixture into the slow cooker, then cover and cook on high for 15 to 20 minutes.
The soup will thicken slightly as the flour cooks and the starches from the potatoes release.

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Season and serve

Taste the soup and add more salt or black pepper if you like a stronger flavor.
Ladle into bowls and garnish with extra black pepper, fresh herbs, or a drizzle of cream.

Olive oil -> unsalted butter: Use the same amount of unsalted butter instead of olive oil for a richer, more savory flavor. Butter helps the vegetables brown slightly and adds a velvety feel to the finished soup.
Heavy cream -> half-and-half: Swap heavy cream for half-and-half if you want a lighter soup that still tastes creamy. Your broth will stay a bit thinner but keeps a soft, silky texture without feeling too rich.
Flour -> cornstarch: Use 1 tablespoon cornstarch mixed with 2 tablespoons cold water instead of the flour for gluten-free thickening. Stir the slurry into the hot soup at the end and simmer until it slightly thickens.

Brown the mushrooms for deeper flavor: If you have time, cook the mushrooms until they take on golden edges before adding the broth. This browning builds savory flavor and keeps the mushrooms from tasting watery in the finished soup.
Cut vegetables the same size: Dice the potatoes and carrots into similar size pieces so they cook through at the same time. Larger chunks will stay firm while smaller pieces may break down too much in the long slow cook.
Use the right slow cooker size: A 4 to 6 quart slow cooker works best for this amount of soup. If your slow cooker is very large, the soup may cook faster and reduce more, so monitor liquid.
Finish with fresh herbs or a touch of acid: Stir in a small handful of chopped fresh parsley or chives right before serving for brightness. A tiny splash of lemon juice can balance the creamy richness and wake up the flavors.

Can I cook this soup on high instead of low?: Yes, you can cook on high for about 3 to 4 hours instead of low. Check the potatoes and carrots after 3 hours so they do not overcook and fall apart.
How do I keep the cream from curdling in the slow cooker?: Always add the heavy cream near the end of cooking, once the vegetables are already tender. Make sure the cream is at room temperature and avoid boiling the soup hard after adding it.
How can I make this soup thicker without flour?: Let the soup cook uncovered on high for 20 to 30 minutes to reduce the liquid slightly. You can also mash some of the potatoes in the pot, which naturally thickens the broth.
Can I freeze leftovers of this soup?: This soup freezes fairly well, but the texture of the potatoes may soften more after thawing. Cool the soup completely, store in freezer-safe containers, and leave some space at the top for expansion. Reheat gently on the stove or in a slow cooker, stirring in a splash of cream if needed.

This cozy crockpot mushroom and potato soup shines with a side of crusty bread or warm garlic toast.

For extra comfort, top each bowl with shredded cheese, more sautéed mushrooms, or crunchy fried onions.

If you want more protein, stir in white beans or leftover rotisserie chicken right before serving.

Ruth, Olathe: Turned out really cozy and flavorful, but next time I’d cut the rosemary back a bit since it started to overpower the mushrooms. — 4 ★

Eunice: Glad it hit that cozy, flavorful spot, Ruth! Next time try cutting the dried rosemary to 1/4 tsp (or even a pinch) so the mushrooms stay front and center. 😊