🧅 French Onion, Cream of Mushroom, Beef Gratin Soup🧀
This French Bistro Creamy Onion, Mushroom & Beef Soup is a rich and comforting French-inspired recipe featuring caramelized sweet onions, earthy mushrooms, delicate slices of beef, Marsala wine, and a silky cream broth finished with melted Gruyère cheese.
This easy bistro-style soup delivers deep slow-cooked flavor without requiring a traditional pot roast, making it perfect for cozy winter dinners, elegant comfort food, and restaurant-quality home cooking. Discover this luxurious creamy French onion-inspired soup recipe at https://www.tretaylor.com
A rich bistro-style comfort soup with golden onions, Marsala, cream, and melted cheese—no bread required
Some recipes begin as leftovers and become legends.
This French bistro–inspired creamy onion and mushroom beef soup combines deeply caramelized sweet onions, earthy mushrooms, finely diced vegetables, and delicate slices of beef in a luscious cream-enriched broth. Finished with gently melted cheese on top, it delivers the warmth of French onion soup without heaviness—elegant, cozy, and perfect for cold evenings.
Serve with a simple baguette on the side if desired, but the soup itself is rich enough to stand beautifully on its own.
🧺 Ingredients
🥩 Velvet Bistro Flavor Foundation ⭐
8–12 oz thinly sliced roast beef or leftover cooked beef (use sparingly—this is not a stew)
4 cups rich beef broth or bone broth
2 tbsp browning liquid (Kitchen Bouquet or similar demi-glace style concentrate)
1 tbsp Worcestershire sauce
🧅 Aromatic Vegetable Base
2 tbsp butter
1 large sweet onion (Visalia or yellow), thinly sliced
1 cup mushrooms, sliced
1 carrot, finely diced
1 celery stalk, finely diced
2 cloves garlic (optional)
1 tsp fresh thyme (or ½ tsp dried)
Salt & pepper to taste
🍷 Creamy Finish
¼ cup Marsala wine
¾–1 cup heavy cream
🧀 Cheese Finish
1 cup shredded Gruyère or aged Swiss
Optional: small amount smoked Gouda for added depth
🔥 Instructions
1️⃣ Build the Flavor Foundation
Melt butter in a Dutch oven or heavy pot over medium heat.
Add sliced onions, diced carrots, and celery with a pinch of salt. Cook slowly until onions turn deeply golden and sweet (15–20 minutes). This step creates the signature French onion flavor.
2️⃣ Add Mushrooms & Aromatics
Add mushrooms, thyme, and garlic if using. Sauté until mushrooms soften and develop a rich color.
3️⃣ Deglaze with Marsala
Pour in Marsala wine and scrape up all browned bits from the pan. Allow alcohol to cook off while flavors deepen.
4️⃣ Create the Rich Broth
Add:
beef broth
browning liquid
Worcestershire sauce
Simmer gently for about 10 minutes.
5️⃣ Add Beef
Slice beef into small, delicate pieces and add to soup. The beef should enhance flavor without overpowering.
Simmer gently for 5–10 minutes.
6️⃣ Finish with Cream
Stir in heavy cream and simmer briefly until silky and luxurious.
Taste and adjust seasoning.
7️⃣ French Bistro Cheese Finish
Ladle soup into oven-safe bowls.
Top with shredded cheese and broil until melted and lightly golden.
(No bread required—serve baguette slices on the side if desired.)
💡 Chef Notes
✨ Browning liquid adds deep roasted flavor without long cooking times
✨ Marsala gives warmth and subtle sweetness
✨ Finely diced vegetables melt into the broth for natural body and richness
✨ The cheese creates a French onion experience while keeping the soup elegant and creamy
