Discover a warm, comforting twist on the classic French onion soup with this French Onion Soup with Mushrooms. Savor the rich, caramelized flavors of sweet onions combined with the earthy depth of mushrooms for a cozy, satisfying meal. Add fresh thyme, a splash of wine and brewed coffee, to create layers of flavor. Finish each bowl with a golden, gooey layer of melted cheese on top of crostini, for a rustic yet elegant touch that’s perfect as a starter or a meal in itself.
Use up the rest of that clamshell of mushrooms, by making my Asparagus Mushroom Soup or Meatball Stuffed Mushrooms recipe. Discover more of my French Onion inspired recipes with my French Onion Chicken Pasta. Take a shortcut on the traditional French Onion process by adding my quick French Onion Soup Rice or Roasted Potatoes with Onion Soup Mix recipes to your collection!
Ingredients
Find below the list of ingredients (and the secret ingredient) I used to make my French Onion Soup with Mushrooms. Use a nice dry wine like a Merlot or Cabernet Sauvignon for this recipe, or find their dealcoholized counterparts at the grocery stores.
- French Baguette for the Crostini
- Butter
- Olive Oil
- Mushrooms: White Button, or Cremini
- Large Sweet Onions
- Garlic
- Fresh Thyme
- Dry Red Wine (Cabernet Sauvignon, Merlot, or Pinot Noir)
- Beef Broth
- Strong Brewed Coffee
- Grated Extra Old White Cheddar (or use the traditional Gruyere)
See recipe card for quantities.
Instructions
Start the French Onion Soup with Mushrooms recipe by making the Crostini. Preheat the oven to 350F and line a baking tray with parchment paper. Cut the baguette in slices and place on the prepared tray. Brush the top of the slices with olive oil and sprinkle them with seasoning. Bake in the preheated oven until lightly golden.
To make the soup, I recommend that you slice the mushrooms and all of the onion before you start cooking the soup.
1. Place a large Dutch oven on medium-high heat. Melt a tablespoon of butter in the pot and add in the sliced mushrooms. Cook fully and then remove from the Dutch oven.
2. Add three tablespoons of butter with olive oil to the pot. Place all of the sliced onions in the Dutch oven and cook on medium-high, stirring constantly. Cook so that the onions start to loose all their water content, soften and reduce.
3. Once the onions lose their water content, reduce the heat to a medium heat. Stir every minute or so for 30-40 minutes, until the onion have a nice caramelized color.
4. Add the minced garlic, thyme, and cooked mushrooms to the caramelized onions. Cook for 2 minutes while stirring.
5. Deglaze the Dutch oven with the wine. Scrape the bottom of the pot to release all of the stuck on flavors.
6. Add the beef broth and the brewed coffee to the Dutch oven. Bring to a simmer and cook for 10 minutes.
7. Pour the French Onion Soup with Mushrooms into oven safe bowls, placing them on a baking tray. Place the prepared crostini to cover the surface of the bowl. Sprinkle the grated cheese over the crostini. Carefully place the tray with soups under the oven broiler to crisp up the cheese.
Substitutions
- Wine - Replace the wine in the recipe with the same amount of broth. Find dealcoholized Cabernet Sauvignon in most large grocery stores, or use red cooking wine.
- Mushrooms - Use any type of mushrooms you have on hand, same quantity.
- Crostini - Substitute the baguette for pieces or slices of sourdough bread.
Storage
Store French Onion Soup with Mushrooms as the soup it self, without the crostini and cheese. Place in airtight containers and refrigerate for 2-3 days, or in the freezer for up to a month.
Recipe
French Onion Soup with Mushrooms
Ingredients
Crostini Ingredients
- 16 slices French Baguette ½ inch slices
- 2 tablespoon Olive Oil
- ½ teaspoon Salt
Soup Ingredients
- ¼ cup butter divided
- 6 pieces Cremini Mushrooms sliced
- 2 tablespoon Olive Oil
- 6 cups Sweet Onion Vidalia or Walla Wallas
- 3 teaspoon Salt
- 4 cloves Garlic finely minced
- ½ tablespoon Thyme Leaves
- 1 cup Dry Red Wine
- 900 ml Beef Broth
- 1 cup Brewed Coffee
- 1 cup Extra Old White Cheddar or Gruyere Cheese grated
Instructions
To Make the Crostini
- Preheat the oven to 350F and line a baking tray with parchment paper. Cut the baguette in slices and place on the prepared tray.
- Brush the top of the slices with olive oil and sprinkle them with seasoning. Bake in the preheated oven until lightly golden.
To Make the Soup
- Place a 4QT Dutch oven on medium-high heat. Melt a tablespoon of butter in the pot and add in the sliced mushrooms. Cook fully and then remove from the Dutch oven.
- Add three tablespoons of butter with olive oil to the Dutch oven. Place all of the sliced onions in the Dutch oven and cook on medium-high, stirring constantly. Cook so that the onions start to loose all their water content, soften and reduce.
- Once the onions lose their water content, reduce the heat to a medium heat. Stir every minute or so for 30-40 minutes, until the onion have a nice caramelized color.
- Add the minced garlic, thyme, and cooked mushrooms to the caramelized onions. Cook for 2 minutes while stirring.
- Deglaze the Dutch oven with the wine. Scrape the bottom of the pot to release all of the stuck on flavors.
- Add the beef broth and the brewed coffee to the Dutch oven. Bring to a simmer and cook for 10 minutes.
- Pour the soup into oven safe bowls, placing them on a baking tray. Place the prepared crostini to cover the surface of the bowl.
- Sprinkle the grated cheese over the crostini. Carefully place the tray with soups under the oven broiler to crisp up the cheese.
