Instant Pot French Onion Soup

French Onion Soup

French Onion Soup (soupe à l’oignon) is a classic French dish. A very popular appetizer many people order at French restaurants.

The base ingredients are simple – onions, stock, bread, and cheese. Sadly, without care, it’s easy to end up with a watery, bland, or flat-tasting soup.

So we carefully crafted and tested our Instant Pot French Onion Soup recipe. Designed with techniques and ingredients that deepen the flavor complexity, body, and textures. Savory-umami, rich, and deliciously flavorful.

Yes. It does take time but the process is easy. 😉

“Zero-Minutes” Pressure Cooking Method

With this French Onion Soup Instant Pot recipe, you’ll see that we set the pressure cooking time to 0 (zero) minutes.

Don’t worry! It’s not a typo.

Setting it at “Zero-Minutes” means we’re using the heat generated during the “pressurizing” stage and the “depressurizing” stage (i.e. during natural release) to cook the onion soup.

How to Make Instant Pot French Onion Soup

Here are the ingredients for cooking French onion soup in Instant Pot:

Onions

Types of Onions: We’re using 3⅔ pounds yellow onions + ⅓ pound shallots. For simplicity, you can use 4 pounds of yellow onions.

Use Good Quality Onions: Since the onions are the star of the show, be sure to use good quality onions. It makes a world of difference!

Deeply Caramelized Onions: Caramelizing the onions is a labor of love. It takes quite a bit of time for the onions to release their sweet flavor, but the process is easy and worth the time! The more caramelized the onions, the more flavors they’ll impart to your Instant Pot French Onion Soup.

• Side Note: It’s our secret weapon for making our beloved Japanese Beef Curry.

Why Add Baking Soda to The Onions?

Baking soda raises the pH and speeds up the rate of maillard reaction.

In simple terms: baking soda helps onions caramelize faster.

This neat trick is from J. Kenji López-Alt (his cookbook is a masterpiece).

Other Ingredients

High-Quality Unsalted Beef Stock. The quality of your stock will determine your French Onion Soup’s destiny to achieve excellence. So, it’s very important to use high-quality beef stock and chicken stock. Have a taste of your stock before you start cooking!

• Substitute with Chicken Stock: If you can’t find high-quality beef stock, you can use all chicken stock or vice versa.
• Substitute with Salted Stock: Keep in mind that the sodium level can vary a lot between different brands. Always taste and adjust accordingly.
• Vegetarian Option: Substitute with vegetable stock.

Fish Sauce & Regular Soy Sauce. Our flavor-boosting, umami-filled secret weapons to elevate our French Onion Soup. They’re not traditional ingredients in a classic French onion soup recipe. But they add a magical boost of savory-umami flavor complexity. Use a high-quality fish sauce – it won’t make the soup taste fishy at all. Give them a shot!

• Fish Sauce Substitute: You can substitute it with soy sauce. Some of our readers like to substitute it with Worcestershire sauce.

Gruyère Cheese. We’re using freshly grated Gruyère cheese with this easy Instant Pot French Onion Soup. It’s a smooth-melting, buttery, full-bodied, complex-flavored cheese from Switzerland.

Unsalted Butter. We prefer to develop recipes using unsalted butter for more control and consistency in the dish’s flavor. If you’re using salted butter, taste and adjust accordingly.

• Vegan Option: Substitute unsalted butter with olive oil.

Sauvignon Blanc. We’re using this bottle of Sauvignon Blanc from Argentina for this French Onion Soup Instant Pot recipe.

Tools for French Onion Soup Instant Pot Recipe

• Instant Pot Pressure Cooker (6qt)
• Pyrex Glass Measuring Cup
• Bamboo Wooden Spoons
• Stainless Steel Grater
• Oven-Safe Bowls

Pressure Cook Onions

Heat up Instant Pot using Sauté More function.

Tip: For older versions, press “Saute” button, then “Adjust” button. For newer versions press “Saute” button twice.

Wait until it says HOT (takes roughly 8 minutes).

Melt 6 tablespoons (64g) unsalted butter in Instant Pot.

Add ⅓ pound (151g) sliced shallot and 3⅙ pounds (1438g) sliced yellow onions in Instant Pot.

Add in ½ teaspoon (2g) baking soda (NOT baking powder), then mix well.

Sauté until onions begin to release moisture. It takes around 5 minutes.

With Venting Knob in Venting Position, close the lid, then turn Venting Knob to Sealing Position.

Pressure cook onions at High Pressure for 20 minutes, then Quick Release.

Caramelize Onions

Open the lid carefully.

There will be a lot of liquid in the Instant Pot. To speed up the process, pour the onion liquid into a large glass measuring cup and reserve it for later.

Caramelize the onions by using the “Saute More” function. Stir occasionally.

Once all the liquid has evaporated, turn the heat down to “Saute Normal”.

At this point, stir the onions more frequently to avoid burning.

Saute onions until they are deep golden brown.

Deglaze Instant Pot

Pour in ¼ cup (63ml) Sauvignon Blanc or dry white wine, then completely deglaze the bottom of the pot with a wooden spoon.

Pressure Cook French Onion Soup

Add minced garlic, 1 tablespoon (15ml) regular soy sauce, 1 tablespoon (15ml) fish sauce, 1 bay leaf, fresh or dried thyme, previously reserved ½ pound (227g) sliced yellow onions, previously reserved onion juice, 4 cups (1L) unsalted beef stock, and 4 cups unsalted chicken stock in the Instant Pot.

Give it a quick mix.

With Venting Knob in Venting Position, close the lid, then turn Venting Knob to Sealing Position.

Instant Pot French Onion Soup Cook Time: Pressure Cook French Onion Soup at High Pressure for 0 (zero) minutes, then Natural Release for 20 minutes.

After 20 minutes of Natural Release, carefully turn Venting Knob to the Venting position to release the remaining pressure.

Once the floating valve drops, remove the lid.

Season and Serve Instant Pot French Onion Soup

While the Instant Pot is natural releasing, preheat oven to 450°F.

Slice French baguette into ¾ to 1-inch thick slices.

Optional – Amy + Jacky’s Flavor Level-Up Tip: Spread some melted butter on the baguette slices, then toast them in the toaster oven.

Taste and season the Instant Pot French onion soup with salt. For reference, we added 3 large pinches of coarse kosher salt.

Optional – Amy + Jacky’s Flavor Level-Up Tip: Simmer the French onion soup in Instant Pot for 5 to 10 minutes using the “Saute” button to give it more body and richness.

Ladle pressure cooker French onion soup into oven-safe bowls.

Place a slice of French baguette on top of the Instant Pot onion soup.

Then layer freshly grated Gruyère cheese on top of the bread.

Place the bowls on a baking tray, then place them in a 450°F oven for 6 to 8 minutes, until the cheese melts and turns golden.

Serve this deliciously flavorful Instant Pot French onion soup immediately.

What to Serve with French Onion Soup

French Onion Soup is a well-loved classic appetizer in French cuisine.

You can pair it with other appetizers like salads, beef tartare, cheese plate, and escargot. Along with main dishes like Instant Pot Beef Bourguignon, Instant Pot Mushroom Risotto, Duck Confit, and Coq au Vin. Then wrap up the meal with Instant Pot Creme Brulee or Instant Pot Crème Caramel.

Other main dishes you can serve with French Onion Soup:

• Beef: Instant Pot Short Ribs, Instant Pot Beef Stroganoff, Instant Pot Roast Beef, Instant Pot Pot Roast, Instant Pot Beef Stew
• Chicken: Instant Pot Chicken Marsala, Instant Pot Whole Chicken, Instant Pot Chicken Cacciatore
• Pork: Instant Pot Pork Chops, Instant Pot Pork Loin

Enjoy the Best Instant Pot French Onion Soup!

More Instant Pot Soup Recipes

• Instant Pot Beef Barley Soup
• Instant Pot Clam Chowder
• Instant Pot Mushroom Soup
• Instant Pot Butternut Squash Soup