There’s an undeniable magic that happens when you marry the deep, earthy flavor of mushrooms with sweetly caramelized onions and gooey, golden cheese. That’s why this Mushroom & Caramelized Onion Soup with Cheesy Toasties has quickly become my favorite comfort-food treat to share with family and friends. Whether you’re craving something spoon-and-bowl cozy on a chilly day or want a dish with true wow-factor for a dinner party, this recipe hits every note—rich, savory soup with rustic, cheesy toasties for dunking. If you love layered flavors and crave nourishing, homemade meals, this is one for the repeat list!
Ingredients You’ll Need
Everything in this recipe serves a purpose, amplifying the essence of classic vegetarian comfort food with minimal fuss. The ingredients are straightforward but work together to create a soup that’s complex, layered, and utterly satisfying, while the toasties bring a guaranteed smile to your face.
- Olive oil (2 tablespoons): Brings a fruitiness and helps onions and mushrooms caramelize beautifully.
- Unsalted butter (2 tablespoons): Adds that luscious, rich mouthfeel and depth to both soup and toasties.
- Yellow onions (2 large, thinly sliced): Slow cooking transforms them into sweet, golden perfection—the backbone of your soup’s flavor.
- Garlic cloves (4, minced): Provides aromatic warmth that lifts and balances the savoriness.
- Cremini or button mushrooms (1 pound, sliced): The star of the show, lending earthy, meaty flavor and heartiness.
- Fresh thyme leaves (1 teaspoon) or dried thyme (1/2 teaspoon): Offers a gentle, woodsy note that complements both onions and mushrooms.
- Dry white wine (1/4 cup, optional): Deglazes the pot for added depth—you can skip it, but it gives a beautiful nuance.
- Vegetable broth (4 cups): Forms the flavorful base that ties everything together; opt for a good quality broth.
- Water (1 cup): Lightens the soup so all those bold flavors can shine through without getting too salty.
- Soy sauce (1 tablespoon): Adds savory umami and a balancing saltiness to the soup.
- Salt and black pepper (to taste): Essential for dialing in the perfect seasoning at the end.
- Heavy cream (1/4 cup, optional): Swirled in for richness right before serving, this is your “velvet touch.”
- Sourdough or rustic bread (4 slices): The hearty base for our toasties; go for the best bread you have.
- Gruyère or sharp cheddar cheese (1 cup, shredded): Melted onto the bread, it’s pure bliss in every bite.
- Butter for toasties (2 tablespoons): Ensures golden, crispy edges on the grilled bread.
How to Make Mushroom & Caramelized Onion Soup with Cheesy Toasties
Step 1: Caramelize the Onions
Start by heating the olive oil and butter together in a large pot over medium heat. Add those thinly sliced onions and let them cook, stirring with patience and love every now and then. Give them a good 25 to 30 minutes—trust me, this is where the magic happens! The onions will turn meltingly soft and an irresistible golden-brown, transforming the soup’s flavor from simple to spectacular.
Step 2: Add Garlic and Sauté
Once your onions look irresistibly caramelized, toss in the minced garlic. Stir continuously and let it cook for just about a minute, until its fragrance fills your kitchen—this small step deepens the base flavor for the Mushroom & Caramelized Onion Soup with Cheesy Toasties, and you’ll notice the difference in the end.
Step 3: Brown the Mushrooms and Add Thyme
Now it’s the mushrooms’ turn to shine. Stir the sliced mushrooms and thyme into the pot, then crank up the heat to medium-high. Sauté for 8 to 10 minutes, stirring often, until the mushrooms shrink and take on a rich, browned color. This transforms their earthy taste into something deeply savory and almost meaty.
Step 4: Deglaze and Simmer
If you have a splash of dry white wine on hand, tip it in and use your spoon to gently scrape up all those browned bits on the bottom of the pot—those bits are pure flavor! If not, don’t worry, the soup will still be delicious. Pour in the vegetable broth, water, and soy sauce. Bring everything to a gentle simmer and let it bubble away for about 15 minutes, giving those flavors extra time to mingle and develop.
Step 5: Season and Blend (If Desired)
Taste your soup and add salt and black pepper as needed. If you love a velvety texture, blend part of the soup using a stick blender or by transferring some to a blender and pulsing (leave some chunks if you like it rustic!). Right before serving, stir in the optional heavy cream for the ultimate silky finish.
Step 6: Make the Cheesy Toasties
Now for the irresistible toasties! Butter one side of each slice of sourdough or rustic bread. Place some cheese on the unbuttered side, then add another slice on top, buttered side out. In a skillet set over medium heat, grill the sandwiches for about 3 to 4 minutes per side, until the bread is golden brown and crispy, and the cheese is gloriously melty. Slice and get ready to dunk!
How to Serve Mushroom & Caramelized Onion Soup with Cheesy Toasties
Garnishes
Garnishing adds both beauty and flavor. Try a sprinkle of fresh thyme or chopped parsley for a burst of color, a grind of black pepper for a peppery finish, or even a drizzle of extra cream swirled on top. For a little extra elegance, a few crispy fried onions or thinly shaved raw mushroom slices can make your soup look restaurant-ready.
Side Dishes
This Mushroom & Caramelized Onion Soup with Cheesy Toasties is hearty on its own, but a crisp green salad with a mustardy vinaigrette makes a lovely, fresh pairing. For something a bit more substantial, serve with roasted root vegetables or a charcuterie-style plate of pickles and olives to cut the richness.
Creative Ways to Present
Serving in wide, shallow bowls lets the soup cool to the perfect temp quickly, and leaves plenty of room to perch those cheesy toasties or float croutons. For more playful entertaining, try cutting the toasties into dippable strips or triangles. And if you’re serving a crowd, consider ladling the soup into espresso cups for a mini starter-sized treat.
Make Ahead and Storage
Storing Leftovers
If you end up with leftovers (lucky you!), let your soup cool completely before storing it in an airtight container in the fridge. It will keep beautifully for up to 4 days, and the flavors actually deepen as it rests—perfect for a quick weeknight lunch or late-night snack. Just keep the cheesy toasties separate so they stay crisp.
Freezing
The base of this Mushroom & Caramelized Onion Soup with Cheesy Toasties freezes like a dream. Skip the cream if you plan to freeze; simply cool the soup, portion into freezer-safe containers, and freeze for up to 3 months. When you’re ready to enjoy, just thaw overnight in the fridge. Freshly-made toasties are always best, so whip those up when you reheat the soup.
Reheating
To reheat, pour the soup into a saucepan and gently warm over medium heat until steaming. If your soup has thickened, loosen it with a splash of water or broth. Add the cream just before serving if you’re using it. Reheat your toasties in a skillet or oven for a few minutes to revive their crispy glory.
FAQs
Can I use a different type Main Course
Absolutely! You can mix button, cremini, shiitake, or even portobello mushrooms for richer flavor and texture. Each one adds its own subtle character, so feel free to experiment with what’s available or in season.
Is the white wine necessary?
No worries if you’d rather skip the wine—the soup will still taste incredible. The wine just adds a little extra depth, but you can simply use a splash of extra broth or even a few drops of balsamic vinegar for a similar effect.
How can I make this dish vegan?
It’s very easy to veganize this recipe! Use olive oil or vegan butter throughout, your favorite unsweetened plant-based cream, and vegan cheese for the toasties. The soup’s inherent umami makes it just as satisfying even without dairy.
What if I don’t have a blender?
No blender? No problem! The Mushroom & Caramelized Onion Soup with Cheesy Toasties is fantastic left chunky. Simply mash a few mushrooms and onions with a potato masher for a bit of smoothness without losing texture.
Can I prepare the toasties ahead of time?
The toasties are best hot and fresh, but you can assemble them ahead and keep them wrapped in the fridge, ungrilled. When ready to eat, grill them straight from the fridge until the cheese is melted and the bread is crisp.
Final Thoughts
If you’re ready for a big bowl of coziness that’s as satisfying for a dinner party as it is for a quiet night in, Mushroom & Caramelized Onion Soup with Cheesy Toasties is the perfect answer. Give it a try, make it your own with your favorite cheeses and mushrooms, and let yourself luxuriate in all those soul-warming flavors. I know this will quickly become one of your cherished go-to recipes!
Print
Mushroom & Caramelized Onion Soup with Cheesy Toasties Recipe
- Prep Time: 15 minutes
- Cook Time: 45 minutes
- Total Time: 1 hour
- Yield: 4 servings
- Category: Main Course
- Method: Stovetop
- Cuisine: American
- Diet: Vegetarian
Description
A cozy and flavorful Mushroom & Caramelized Onion Soup paired with Cheesy Toasties, perfect for a comforting meal. This vegetarian dish combines earthy mushrooms, sweet caramelized onions, and gooey cheese on crispy toast.
Ingredients
Soup:
- 2 tablespoons olive oil
- 2 tablespoons unsalted butter
- 2 large yellow onions, thinly sliced
- 4 garlic cloves, minced
- 1 pound cremini or button mushrooms, sliced
- 1 teaspoon fresh thyme leaves (or 1/2 teaspoon dried thyme)
- 1/4 cup dry white wine (optional)
- 4 cups vegetable broth
- 1 cup water
- 1 tablespoon soy sauce
- Salt and black pepper to taste
- 1/4 cup heavy cream (optional)
Cheesy Toasties:
- 4 slices sourdough or rustic bread
- 1 cup shredded gruyère or sharp cheddar cheese
- 2 tablespoons butter
Instructions
- Soup: Heat olive oil and butter in a large pot, caramelize onions, add garlic, mushrooms, thyme, cook, deglaze with wine, add broth, water, soy sauce, simmer, season, blend if desired, stir in cream.
- Cheesy Toasties: Butter one side of each bread slice, top with cheese, grill in skillet until golden brown and cheese is melted.
Notes
- Use a mix of mushrooms for deeper flavor.
- You can skip the cream for a lighter, dairy-free option.
- Add a splash of balsamic vinegar for extra depth.
- Gruyère adds a nutty richness to the toasties, but any melty cheese works.
Nutrition
- Serving Size: 1 bowl soup + 1 toastie
- Calories: 430
- Sugar: 7g
- Sodium: 680mg
- Fat: 27g
- Saturated Fat: 13g
- Unsaturated Fat: 12g
- Trans Fat: 0g
- Carbohydrates: 30g
- Fiber: 4g
- Protein: 12g
- Cholesterol: 45mg
