📝 About This Recipe
Transport your kitchen to a cozy Parisian bistro with this deeply savory, mahogany-hued classic, reimagined for the modern pressure cooker. By utilizing the Instant Pot, we achieve the complex, jammy sweetness of slow-caramelized onions in a fraction of the time, infused with rich beef bone broth and a splash of dry sherry. Each bowl is crowned with a crusty baguette crouton and a bubbling, molten layer of nutty Gruyère cheese for the ultimate comfort food experience.
🥗 Ingredients
The Onion Base
- 3 pounds Yellow Onions (halved and thinly sliced into half-moons)
- 4 tablespoons Unsalted Butter (high-quality European style preferred)
- 1 tablespoon Olive Oil (to prevent butter from burning)
- 1/2 teaspoon Granulated Sugar (to aid in rapid caramelization)
- 1 teaspoon Kosher Salt (plus more to taste)
The Broth & Aromatics
- 6 cups Beef Bone Broth (low sodium, high quality)
- 1/2 cup Dry Sherry (or dry white wine like Sauvignon Blanc)
- 1 tablespoon Worcestershire Sauce (for umami depth)
- 4-5 sprigs Fresh Thyme (tied with kitchen twine)
- 2 pieces Bay Leaf (dried)
- 3 cloves Garlic (minced)
- 1/2 teaspoon Black Pepper (freshly cracked)
The Topping
- 1 loaf French Baguette (cut into 1-inch thick slices)
- 1.5 cups Gruyère Cheese (freshly grated)
- 1/4 cup Parmesan Cheese (freshly grated for a salty bite)
👨🍳 Instructions
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1
Set your Instant Pot to the 'Sauté' function on the 'High' or 'More' setting. Add the butter and olive oil, allowing the butter to melt and begin to foam.
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2
Add the sliced onions to the pot. Stir well to coat them in the butter and oil. Sprinkle with the salt and sugar; the salt helps draw out moisture while the sugar encourages browning.
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3
Sauté the onions for 10-15 minutes, stirring occasionally. You want them to soften significantly and start turning a light golden brown. If they stick too much, add a tablespoon of water to deglaze.
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4
Add the minced garlic and cook for just 1 minute until fragrant. Do not let the garlic burn, as it will turn the soup bitter.
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5
Pour in the dry sherry. Use a wooden spoon to scrape all the brown bits (the fond) off the bottom of the pot. This is where the deep flavor lives!
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6
Add the beef broth, Worcestershire sauce, thyme sprigs, bay leaves, and black pepper. Stir to combine.
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7
Secure the lid and set the valve to the 'Sealing' position. Cancel the Sauté function and select 'Manual' or 'Pressure Cook' on High Pressure for 20 minutes.
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8
While the soup cooks, preheat your oven to 400°F (200°C). Place baguette slices on a baking sheet and toast for 3-5 minutes per side until crisp and lightly golden.
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9
Once the pressure cooking time is complete, allow for a 'Natural Release' for at least 10 minutes, then carefully turn the valve to 'Venting' to release any remaining steam.
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10
Open the lid and remove the thyme sprigs and bay leaves. Taste the broth and adjust seasoning with extra salt or pepper if needed.
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11
Switch the oven to 'Broil'. Ladle the hot soup into oven-safe crocks or ramekins, leaving about half an inch of space at the top.
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12
Place one or two toasted baguette slices on top of each bowl. Generously pile the grated Gruyère and Parmesan over the bread, allowing some to spill over the edges.
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13
Place the crocks on a baking sheet and broil for 2-4 minutes, watching closely, until the cheese is melted, bubbly, and sports beautiful brown spots.
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14
Remove from the oven and let sit for 2 minutes (the bowls will be very hot!). Serve immediately with a sprig of fresh thyme for garnish.
💡 Chef's Tips
For the best flavor, use a mix of onions like yellow, white, and red to create a more complex sweetness. Always grate your own cheese; pre-shredded cheeses are coated in potato starch which prevents that perfect, gooey melt. If your soup looks too light after pressure cooking, use the Sauté function for 5 minutes at the end to reduce and deepen the color. Don't skip the toasted bread step; untoasted bread will turn into soggy mush immediately upon hitting the broth. To make it vegetarian, substitute the beef broth with a dark mushroom broth and use a vegetarian-friendly Worcestershire sauce.
🍽️ Serving Suggestions
Pair with a crisp, chilled glass of French Chablis or a dry Apple Cider to cut through the richness. Serve alongside a simple butter lettuce salad with a sharp Dijon vinaigrette. A side of roasted marrow bones makes this an incredibly decadent, restaurant-style meal. For a lighter touch, serve with a plate of fresh cornichons and spicy radishes. Finish the meal with a light lemon sorbet to cleanse the palate after the heavy cheese and beef flavors.