If you ask me, there’s nothing better than a warm bowl of soup when the weather turns cool.
This hearty wild mushroom, caramelized onion and kale soup makes a comforting dinner that’s packed with earthy flavors. Sweet caramelized onions pair with meaty mushrooms and tender kale in a rich, savory broth.
The mushrooms get seared until golden while the onions cook low and slow until they’re perfectly sweet. Fresh kale wilts right into the soup, adding color and nutrients to every spoonful.
It’s a satisfying meal that feels fancy but comes together easily, perfect for cozy weeknight dinners.
Why You’ll Love This Wild Mushroom, Caramelized Onion and Kale Soup
- Packed with nutrients – The combination of kale, mushrooms, and onions gives you a powerhouse of vitamins and antioxidants in every spoonful.
- Rich, earthy flavors – The caramelized onions and wild mushrooms create a deep, satisfying taste that feels like a warm hug in a bowl.
- Simple, wholesome ingredients – You probably already have most of these ingredients at home, and they’re all real food without any processed additives.
- Ready in under an hour – This comforting soup comes together quickly, making it perfect for busy weeknights when you want something healthy and filling.
- Naturally gluten-free – Using organic, gluten-free broth makes this soup suitable for those avoiding gluten without sacrificing any flavor.
Which Mushrooms Work Best?
This recipe calls for a mix of shiitake and baby bella (or cremini) mushrooms, which creates a nice balance of earthy flavors and textures.
Shiitake mushrooms bring a deeper, more savory taste, while baby bellas add a mild, meaty quality to the soup.
If you can’t find shiitakes at your local store, you can substitute with portobello mushrooms cut into smaller pieces, or even use all baby bellas if that’s what you have on hand.
Substitute Options
- Shiitake and baby bella mushrooms: You can mix and match any mushrooms you find – portobello, oyster, or even regular white button mushrooms work great. If using dried mushrooms, rehydrate them first and save that soaking liquid to add extra flavor to your broth.
- Kale: Not a kale fan? Spinach, Swiss chard, or collard greens make good substitutes. Just add spinach at the very end since it wilts quickly, while tougher greens like collards might need a few extra minutes to soften.
- Coconut milk: Heavy cream, half-and-half, or even cashew cream can replace coconut milk if you want a different flavor profile. Start with less and add more to taste since these tend to be richer.
- Chicken or vegetable broth: Either broth works fine, but stick with vegetable broth to keep it vegetarian. You can also use mushroom broth for extra earthy flavor – just reduce the salt since it tends to be saltier.
- Sweet onion: Yellow or white onions work just as well, though they might have a slightly sharper bite. The caramelizing process will mellow them out either way.
Can I Make This Soup in a Slow Cooker?
Absolutely.
- Sauté the onions, garlic, and mushrooms as directed, then transfer to the slow cooker.
- Add the broth and kale, then cook on LOW for 4–5 hours or on HIGH for 2–3 hours until the kale is tender.
- Stir in the coconut milk or cream before serving.
Cooking Mistakes to Watch Out For
Be careful not to rush the caramelization process of the onions when preparing this soup. True caramelized onions take at least 20-30 minutes of slow, patient cooking over medium-low heat to develop their sweet, golden flavor.
Another mistake is adding the kale too early, which turns it into mushy, overcooked greens instead of tender leaves with some texture – stir it in during the last 5 minutes of cooking time.
Don’t crowd your mushrooms in the pan or they’ll steam instead of getting that nice golden-brown color, so cook them in batches if needed and make sure your pan is hot before adding them.
What to Serve With Wild Mushroom, Caramelized Onion and Kale Soup?
This earthy, hearty soup pairs beautifully with a thick slice of crusty sourdough or whole grain bread for dipping into all that rich, savory broth.
I love serving it alongside a simple arugula salad with lemon vinaigrette to balance out the deep mushroom flavors, or you could go with some warm dinner rolls if you want something more filling.
For a cozy dinner, try adding some grilled chicken or turkey sausage right into the soup to make it a complete meal. The soup also works great as a starter before roasted chicken or pork tenderloin if you’re planning a bigger dinner.
Storing Instructions
Refrigerate: This hearty mushroom soup keeps really well in the fridge for up to 5 days in an airtight container. The flavors actually get even better after a day or two, so it’s perfect for meal prep. I love having a big batch ready to go for quick lunches during busy weeks.
Freeze: You can freeze this soup for up to 3 months in freezer-safe containers or bags. Just let it cool completely first and leave a little room at the top for expansion. The coconut milk might separate a bit when frozen, but it comes back together beautifully when you reheat it.
Reheat: Warm it up gently on the stovetop over medium-low heat, stirring occasionally until heated through. If you’re using the microwave, heat it in 30-second intervals and stir between each one. Give it a good stir if the coconut milk has separated – it’ll blend right back in.
| Preparation Time | 10-15 minutes |
| Cooking Time | 40-50 minutes |
| Total Time | 50-65 minutes |
| Level of Difficulty | Easy |
Estimated Nutrition
Estimated nutrition for the whole recipe (without optional ingredients):
- Calories: 350-450
- Protein: 8-12 g
- Fat: 24-32 g
- Carbohydrates: 28-36 g
Ingredients
For the soup base:
- 2 tbsp extra-virgin olive oil
- 1 large sweet onion, sliced 1/2 inch thick
- 4 cloves garlic, finely chopped
- 1 tsp sea salt or pink salt
- 1/2 tsp freshly cracked black pepper
- 2 cups whole shiitake mushrooms
- 2 cups baby bella or cremini mushrooms, sliced
- 4 cups organic chicken broth or vegetable broth, gluten-free
- 2 cups loosely chopped kale leaves
For finishing:
- 1/2 cup coconut milk or coconut cream
Step 1: Sauté the Onions
- 2 tbsp extra-virgin olive oil
- 1 large sweet onion, sliced 1/2 inch thick
Heat the extra-virgin olive oil in a large pot over medium heat.
Add the sliced sweet onion and sauté, stirring occasionally, until the onions are golden brown and caramelized, about 10-15 minutes.
This step brings out the natural sweetness of the onions.
Step 2: Add Garlic, Salt, and Pepper
- 4 cloves garlic, finely chopped
- 1 tsp sea salt or pink salt
- 1/2 tsp freshly cracked black pepper
Stir in the finely chopped garlic, sea salt or pink salt, and freshly cracked black pepper.
Continue to cook for 1-2 minutes until the garlic becomes fragrant, being careful not to let it burn.
Step 3: Cook the Mushrooms
- 2 cups whole shiitake mushrooms
- 2 cups baby bella or cremini mushrooms, sliced
Add the whole shiitake mushrooms and the sliced baby bella or cremini mushrooms to the pot with the sautéed onions, garlic, and seasoning.
Cook for about 5-7 minutes, stirring occasionally, until the mushrooms are softened and begin to turn golden.
I like to let the mushrooms get a little golden for extra flavor.
Step 4: Add Broth and Kale, Then Simmer
- 4 cups organic chicken broth or vegetable broth, gluten-free
- 2 cups loosely chopped kale leaves
Pour in the chicken or vegetable broth, stirring to combine with the sautéed mushroom mixture.
Bring everything to a boil, then add the loosely chopped kale leaves.
Reduce the heat to low, cover the pot, and let it simmer for 20 minutes so the flavors meld and the kale becomes tender.
Step 5: Finish with Coconut Milk and Adjust Seasoning
- 1/2 cup coconut milk or coconut cream
Uncover the pot and stir in the coconut milk or coconut cream.
Let the soup heat through for a minute or two.
Taste and season with additional salt and pepper if needed before serving.
For a richer soup, I sometimes use coconut cream instead of milk.
Comforting Wild Mushroom, Caramelized Onion and Kale Soup
Ingredients
For the soup base:
- 2 tbsp extra-virgin olive oil
- 1 large sweet onion, sliced 1/2 inch thick
- 4 cloves garlic, finely chopped
- 1 tsp sea salt or pink salt
- 1/2 tsp freshly cracked black pepper
- 2 cups whole shiitake mushrooms
- 2 cups baby bella or cremini mushrooms, sliced
- 4 cups organic chicken broth or vegetable broth, gluten-free
- 2 cups loosely chopped kale leaves
For finishing:
- 1/2 cup coconut milk or coconut cream
Instructions
- Heat the extra-virgin olive oil in a large pot over medium heat. Add the sliced sweet onion and sauté, stirring occasionally, until the onions are golden brown and caramelized, about 10-15 minutes. This step brings out the natural sweetness of the onions.
- Stir in the finely chopped garlic, sea salt or pink salt, and freshly cracked black pepper. Continue to cook for 1-2 minutes until the garlic becomes fragrant, being careful not to let it burn.
- Add the whole shiitake mushrooms and the sliced baby bella or cremini mushrooms to the pot with the sautéed onions, garlic, and seasoning. Cook for about 5-7 minutes, stirring occasionally, until the mushrooms are softened and begin to turn golden. I like to let the mushrooms get a little golden for extra flavor.
- Pour in the chicken or vegetable broth, stirring to combine with the sautéed mushroom mixture. Bring everything to a boil, then add the loosely chopped kale leaves. Reduce the heat to low, cover the pot, and let it simmer for 20 minutes so the flavors meld and the kale becomes tender.
- Uncover the pot and stir in the coconut milk or coconut cream. Let the soup heat through for a minute or two. Taste and season with additional salt and pepper if needed before serving. For a richer soup, I sometimes use coconut cream instead of milk.
