Low-Carb Instant Pot Leek and Cauliflower Soup Recipe

If you’re searching for a delicious low carb soup, this Instant Pot Leek & Cauliflower Low Carb Soup is a winner. My family — even our picky eater — devoured it. It’s creamy, satisfying, and packed with vegetable flavor.

Instant Pot Low Carb Soup

When cold weather arrives, the Instant Pot becomes our go-to for quick, comforting meals. We use it often for soups — the speed and hands-off convenience make it perfect for busy days. The Instant Pot lets you sauté, pressure cook, and then keep the soup warm without babysitting a pot on the stove. Start the program, step away, and come back when it’s done. The “keep warm” setting is particularly handy if you need to have lunch ready for kids after activities — the soup stays hot and ready to serve.

Cauliflower Soup For the Low Carb Win

Cauliflower is a staple for low carb cooking — from mashed cauliflower to rice and creamy soups. Paired with leeks, it becomes a fragrant, silky soup that feels indulgent without the carbs. I kept this version cheese-free, but a sharp Swiss or a sharp cheddar stirred in at the end would be a delicious option if you prefer a cheesier flavor.

The trick to keeping the soup low carb is using heavy whipping cream instead of milk. Heavy cream provides richness with fewer carbs, and the soup thickens naturally when blended, so no additional thickeners are needed.

Using Leeks in Soup

Leeks add a mild, onion-like sweetness, but they require a bit of care. A few simple tips:

1. Trim off the tough dark green tops and use the white and pale green parts. The paler sections are tender and flavorful — a little light green is fine to include.
2. Leeks often hold grit between their layers. After trimming, slice and rinse them thoroughly to remove any dirt.
3. Like onions, leeks benefit from being softened before simmering. When sautéed in the Instant Pot they’ll soften quickly, so this step is easy to manage.

There you go — a comforting, low carb cauliflower and leek soup that’s simple to make and full of flavor. I always end up with a couple of leeks left in the bunch, which just means more soup later in the week.

Happy low carbing,

Mike