Easy Broccoli Cheddar Soup (Instant Pot / Slow Cooker)

• Oil and Aromatics: I use garlic-infused olive oil and leek greens for low FODMAP. Otherwise, you can use extra virgin olive oil, fresh minced garlic, and white onion instead.
• Butter (Optional): To add extra richness to the soup, I add some unsalted butter or ghee (clarified butter), but this is optional.
• Broth: When making vegetarian broccoli cheese soup, I use vegetable broth (homemade or store-bought). Or, you can use chicken bone broth (homemade or store-bought). If needing low FODMAP, make sure the broth you use is compliant.
• Broccoli: You can use fresh or frozen broccoli when making this recipe at the same amount of cooking time. Using frozen broccoli makes this recipe so much easier as it is pre-chopped, and you don't have to worry about it going bad quickly. If needing low FODMAP, make sure you only use the florets or heads of the broccoli as the stems are higher in FODMAPs per Monash University's Low FODMAP Diet App. Otherwise, you can use a combination of broccoli florets and stems.
• Herbs and Spices: Don't let the long list of herbs and spices deter you from making this recipe as they are actually really quick to measure out. I use dried chives (optional if using onion), fresh or dried thyme, nutritional yeast (optional - adds extra cheesy flavor and nutrients), sea salt and black pepper, smoked paprika, and ground nutmeg (optional, although it adds extra warmth that I love).
• Mustard: I add Dijon mustard, which adds some tangy flavor. If needing low FODMAP, make sure the Dijon mustard you use is garlic and onion-free.
• Cream: I use heavy cream, which brings the best consistency, richness and flavor for broccoli cheese soup. Use lactose-free heavy cream if needed.
• Cheese: I typically opt for medium sharp cheddar cheese that I shred myself using a box grater. Store-bought shredded cheese typically contains more carbs and additives. I've also tested this recipe with sharp cheddar and old cheddar, noticing very little difference in flavor.
• Thickener (Optional): The soup may be thick enough for you without adding a thickener. If you prefer a thicker soup, to keep it flourless, gluten-free and grain-free, use xanthan gum. Feel free to use other thickeners (quantities will vary).

Ingredient quantities and preparation instructions are in the recipe card below.

How to Make Broccoli Cheddar Soup

Here's how to make broccoli soup with cheddar cheese in the Instant Pot (pictured) or slow cooker:

1. Sauté Aromatics: For the Instant Pot, press “Sauté.” For the slow cooker, heat a large skillet over medium heat. Once hot, add oil and butter (if using), swirling to coat. If using garlic, sauté for 30 seconds, stirring constantly. Add leek greens (or onion) and cook until softened, about 2 minutes (4-5 minutes if using onion).
2. Deglaze: Hit "Cancel" on the Instant Pot. Pour in 1 cup of the broth, scraping up any browned bits on the bottom with a plastic spoon or spatula. If using a slow cooker, transfer everything to it now.
3. Build the Flavor: Stir in dried chives (if using), nutritional yeast (if using), thyme, salt, pepper, smoked paprika, nutmeg (if using), and Dijon mustard. Add the chopped broccoli and remaining 2 cups of broth and stir again.
4. Cook the Soup:
   • Instant Pot: Secure the lid, set to Pressure Cook (Manual) for 5 minutes, then do a quick release.
   • Slow Cooker: Cover and cook on low for 4-6 hours or high for 2-3 hours, until the broccoli is tender and luscious.

5. Blend for Creaminess: Remove the lid and ladle out half the soup into a large bowl. Blend the remaining soup using an immersion blender (recommended), regular blender, or potato masher. Stir in the reserved portion for a mix of creamy and chunky textures.
6. Add the Cream: Set the Instant Pot to "Sauté" on low heat or the slow cooker to high. Stir in the heavy cream and let the soup warm until it begins to simmer.
7. Melt the Cheese: Once simmering, add the cheddar ½ cup at a time, stirring constantly until fully melted. Scrape the bottom occasionally with your spatula to prevent clumping. If using a slow cooker, cook on high for an additional 30 minutes, stirring occasionally.
8. Thicken (Optional): For a thicker soup, sprinkle xanthan gum over the top while stirring until the desired thickness is reached, or use your thickener of choice. Press “Cancel” on the Instant Pot or turn off the slow cooker.