Instant pot Caramelized Mushroom Onion soup

This easy caramelized onion soup with mushrooms is the perfect cozy dinner recipe. Making it in an Instant Pot cuts the cooking time in half!

Ingredients

Full recipe and amounts can be found in the recipe card below.

• Onions. I used regular white onions but you can use any variety you have.
• Brown sugar. 
• Mushrooms. I used portabellini/chestnut mushrooms but any mushrooms will work.
• Garlic. 
• Thyme. 
• Red wine. 
• Flour. 
• Balsamic vinegar. 
• Beef stock. The beef stock contributes to the rich flavor and color of the finished soup however any stock can be substituted. To keep this soup vegetarian/vegan, substitute with rich mushroom stock if you can.
• Salt and pepper. 

How to make caramelized onion soup in an Instant Pot

1. Prep the ingredients: Slice the onions thinly then cook in the Instant Pot on the saute setting for 7-10 minutes until the onions start to brown. While the onions are browning, clean and slice the mushrooms and finely chop/crush the garlic.
2. Make the soup: Once the onions are golden brown, add the sugar and cook for another minute or two then add the mushrooms, garlic and thyme. Allow to saute for a few minutes then stir in the flour. Pour in the wine and Balsamic vinegar and allow to come to a simmer. Pour in the beef stock and season generously. Cover with the lid (make sure it’s in the sealing position) then cook the soup on high pressure for 7 minutes.
3. Serve: Once the soup has cooked, quick release the pressure. Taste and adjust seasoning if necessary then serve with your bread of your choice. I served the soup with cheesy toasts which worked perfectly with the delicious soup.

Stove-top instructions

1. Brown the onions in a large pot set over medium-high heat for 7-10 minutes. Add the sugar and cook for 2 minutes then add the garlic, thyme and mushrooms. Cook for 5 minutes. Stir in the flour then pour in the wine and vinegar. Bring to a simmer then pour in the stock and season. Partially cover with a lid and bring to a simmer. Allow to cook for 25-30 minutes.
2. Once the soup has cooked, Adjust the seasoning if necessary then serve with bread of your choice.

What to serve with onion soup

1. Easy focaccia bread
2. Cheese and herb Irish soda bread
3. Easy crusty bread

Soup recipes

1. Instant pot chicken black bean soup
2. Easy tomato soup with grilled cheese
3. Easy healthy chicken broccoli soup