I have a thing for onions. Between French Onion Chicken, French Onion Soup and French Onion Risotto, I’ve learned how to coax incredible depth and sweetness from humble onions. That love of alliums and a longtime fondness for creamy comfort soups led me to ask a simple question: why not a true Cream of Onion? That idea sparked this recipe, and I can promise you—this version is heavenly. It’s rich and silky, distinctly onion-forward without being sharp, and finished with cheese for a luxurious mouthfeel. Make it in the Instant Pot for speed and convenience, and you’ll soon find it on repeat.
This soup balances sweet, caramelized onion flavor with creamy texture and savory seasoning. Potatoes add body and natural starch to thicken the base, while cream and a soft cheese (Boursin or cream cheese) round everything out. A small amount of Sherry brightens the profile, and a final topping of deeply caramelized onions and melted cheese elevates each bowl into something special.
Below I’ll walk through how I built this soup, step by step, alongside the photos showing the process. Follow the method and you’ll have a bowl of comforting, restaurant-quality Cream of Onion that’s surprisingly easy to prepare.
Start with a mix of onions for complexity—sweet Vidalia, yellow and red onions each contribute different layers of flavor. Slice them into thin strips so they soften and break down uniformly.
Alongside the onions, prepare starchy potatoes. Peel and cut them into chunks; they help thicken the soup when puréed and add a smooth body without overpowering the onion character.
Set the Instant Pot to Sauté on high. Add olive oil and butter to the insert and let the butter melt until it begins to sizzle. The combination of butter and oil provides flavor and raises the smoke point for better browning.
Toss in all the sliced onions. They may seem to overflow the pot at first, but they will soften and reduce substantially as they cook. Stir to coat them in fat, then let them cook, stirring periodically, until they collapse into a rich, jammy mass. This step builds the soup’s foundational flavor and should not be rushed.
Once the onions are deeply softened and developing buttery ribbons, add garlic briefly to release its aroma, then add the potato chunks. Pour in broth, a splash of Sherry for brightness (or extra broth if you prefer no alcohol), dried thyme and seasoned salt. Stir, secure the lid, and pressure cook on high for 10 minutes. Quick-release when the time is up.
While the soup cooks, caramelize a few additional onions in a skillet with a bit more oil. Cook them over medium-high heat until they are deeply browned, slightly charred at the edges and syrupy—this step adds the best possible finishing garnish and contrast to the silky base.
When you remove the lid from the Instant Pot, scoop out and reserve a cup or two of the soft cooked onions (leave the potatoes in the pot). These reserved pieces will be reincorporated later for texture and onion bursts.
Purée the remaining contents of the pot with an immersion blender until smooth and velvety. If you don’t have an immersion blender, transfer batches to a countertop blender, but blending directly in the pot is faster and cleaner.
To thicken and finish the soup, whisk in a small amount of flour to remove any raw edges, then stir in heavy cream (or half-and-half) and a soft cheese such as Boursin or cream cheese until completely melted and incorporated. Season with onion powder and garlic salt to taste. Fold in the reserved cooked onions and chopped chives for freshness.
Ladle the soup into bowls and top each serving with the skillet-caramelized onions and a sprinkle of shredded Mozzarella or Swiss. The cheese will melt into the hot soup, adding a pleasing stretch and a glossy finish. If you want to be indulgent, serve it in a sourdough bread bowl and broil briefly for a gratin-style top.
This Cream of Onion is a crowd-pleaser—creamy, richly savory and layered with the caramelized sweetness of slow-cooked onions. It’s comforting, impressive, and perfect for cold nights or anytime you want a bowl of cozy luxury. Just be warned: its irresistible aroma might make it a risky choice for first dates.
CREAM OF ONION SOUP — a true game changer.
Instant Pot Cream of Onion Soup
Cream of Onion rivals a classic French onion with a silky texture and cheese blended into the soup. For a show-stopping finish, add a crouton and melted cheese topping.
5 minutes
53 minutes
58 minutes
Ingredients
- 1 stick (8 tbsp) salted butter
- 2 tbsp olive oil
- 8 onions for the soup, cut into strips (suggested: 2 Vidalia/sweet, 2 Spanish, 2 yellow, 2 red)
- 2–3 onions for the caramelized topping (suggested: 2 yellow and 1 Vidalia/sweet)
- 1 tbsp crushed garlic
- 2 lbs Idaho/Russet potatoes, peeled and cut into chunks
- 5 cups garlic and/or chicken broth (or equivalent bouillon + water)
- 1/2 cup Sherry wine (or an additional 1/2 cup broth)
- 2 tsp dried thyme
- 1 tbsp seasoned salt
- 1/3 cup all-purpose flour
- 1 cup heavy cream or half-and-half
- 5.2 oz Boursin cheese (or 5 oz cream cheese)
- 2 tbsp onion powder
- 1 tsp garlic salt
- 1/3 cup chives, chopped
- Shredded Mozzarella or Swiss cheese for topping
Instructions
- Set the Instant Pot to Sauté on High (More/High). Add the butter and oil and heat until sizzling.
- Add all the sliced onions, coat them in the butter and oil, and cook while stirring occasionally for about 25 minutes, until they are softened and jammy. This step is important for developing flavor.
- Add the garlic and cook for another minute, then add the potatoes.
- Pour in the broth, Sherry, seasoned salt and thyme. Stir well, secure the lid, and pressure cook on High for 10 minutes. Quick release when done.
- Optional: while the soup cooks, caramelize the additional 2–3 onions in a skillet with 2 tbsp oil over medium-high heat for 20–25 minutes until very browned and syrupy. Set aside.
- When the lid is off, reserve about 1.5–2 cups of the cooked onions from the pot (not the potatoes) and set them aside. Whisk the flour into the reserved onions to remove lumps, if desired.
- Use an immersion blender to purée the remaining soup in the pot until smooth and thickened, about 1–2 minutes.
- Stir in the heavy cream, onion powder, garlic salt and Boursin or cream cheese. Whisk until fully incorporated. You may briefly re-blend if needed for smoothness.
- Add back the reserved onions and chopped chives, stirring to combine.
- Ladle into bowls and top each serving with the caramelized skillet onions and a sprinkle of shredded Swiss or Mozzarella. Serve in a sourdough bowl if you like.
- Enjoy.
Jeffrey’s Tips
For a lower-carb version, substitute chopped cauliflower for the potatoes. Serving the soup in a sourdough bread bowl adds drama and texture. The skillet-caramelized onions are worth the extra time—they provide a sweet, almost smoky counterpoint to the silky base. An immersion blender makes puréeing easier and cleaner since you can blend directly in the pot.