Caramelized Onion & Mushroom Soup

Thick and creamy, this Caramelized Onion and Mushroom Soup is full of rich flavors from sweet caramelized onions, savory mushrooms, and a touch of cream. Easy to make and packed with umami, it’s a treat for any mushroom and onion lover.

This soup might not win any beauty contests, but its taste more than makes up for it! It has a silky texture, deep flavors, and it’s gluten-free. The secret is in the caramelized onions and the combination of mushrooms with a creamy finish. Ready to dig in?

Ingredients

• Butter — Salted, adjust seasonings at the end.
• Onions — Yellow cooking onions.
• Cremini mushrooms — White mushrooms can be used but with less flavor.
• Garlic — Fresh, minced.
• White wine — Adds richness; optional but recommended.
• Beef broth — Low or no sodium.
• Chicken broth — Homemade or store-bought.
• Thyme — Fresh sprigs.
• Cream — Heavy whipping cream.
• Bacon or Pancetta — Crisped, for topping.
• Salt and pepper — To taste; use white pepper for a clean look.

How To Make Caramelized Onion & Mushroom Soup

1. Melt butter in a large pot. Add onions, reduce heat, and cook slowly until they turn a deep caramel color, stirring frequently.
2. Add sliced mushrooms to the onions and sauté until softened.
3. Stir in garlic and cook for another minute.
4. Pour in the white wine and simmer until mostly evaporated.
5. Add chicken broth, beef broth, and thyme. Cover and let simmer for about 10 minutes.
6. Cook the bacon or pancetta until crispy, while the soup simmers.
7. Transfer the soup to a blender, reserving about 1 cup of the chunky onions and mushrooms. Blend until smooth.
8. Return the blended soup to the pot with the reserved chunks. Stir in the cream, season with salt and pepper, and garnish with crumbled bacon or pancetta.

Step-By-Step Process

Chef Jenn’s Tips

• Caramelizing onions takes time, so you can do this step ahead and store them in the fridge.
• They add more flavor than white mushrooms. If using portobellos, remove the gills to avoid discoloration.
• Combining chicken and beef broth gives a balanced flavor.
• When blending hot soup, remove the center lid plug and cover with a towel to avoid splatters.

Variations

• Thicken the Soup: Mix 1 tablespoon of flour with 3 tablespoons of water and add to the soup before pureeing.
• Make It Vegan: Swap the broths with vegetable broth, butter with olive oil, and cream with a non-dairy substitute. Top with toasted nuts instead of bacon.
• Chunky Style: Leave the soup unblended for a heartier texture.

Make It A Meal

Pair this Caramelized Onion and Mushroom Soup with a warm pastrami sandwich or French dip slider. It’s also delicious with a simple pasta salad for a more filling meal.

Storage

Store leftovers in an airtight container in the fridge for 3-4 days. For longer storage, freeze the soup in a freezer-safe container for up to 3 months.