Melt the butter in a Dutch oven or large saucepan over medium-high heat. Sauté the onion, leek, celery, cauliflower, and garlic until the vegetables begin to soften; 7-8 minutes.
Add the chicken broth and bay leaf; cover and simmer for 10 minutes. Add the heavy cream; cover and simmer until the vegetables are tender, approximately 10-15 minutes.
Remove the bay leaf and puree the soup with a stick blender or food processor for 2 minutes or until silky smooth. Season to taste.
In a separate pan heat the avocado oil over medium-high heat and lightly fry the ham until crispy. Set aside to drain on some paper towel.
Using the same pan fry the celery leaves until crisp. Drain the leaves on a piece of paper towel. Divide the soup between serving bowls and top with ham croutons, crème frâiche, fresh herbs, and fried celery leaves.
INSTANT POT® METHOD
Place all the ingredients into the pot. Set to Pressure Cook/High Heat/13 minutes. When finished allow natural release for 5 minutes before triggering quick release. Follow from step 3 in the conventional method.
SLOW COOKER OR STOVE TOP METHOD
Place all the ingredients into the slow cooker; cook on low for 4-5 hours or high for 2-3 hours. Follow from step 3 above.
For stovetop, turn down to low, cover with a lid and cook on low checking every hour until hemp is soft and ham is falling off the bone. Follow from step 2 in the Instant Pot method.
Add the butter, onion, leek, celery, cauliflower, and garlic, into the mixer; chop 4 sec/speed 6. Scrape down the sides of the bowl.
Add the remaining ingredients to the mixer (filling only to the max line with broth); set to slow cook/100min/95°C (or 100 min/95°C/reverse/stir).
Discard the bay leaf and puree the soup in two batches; 30sec/speed 5-9 (or less if you prefer the soup slightly chunky). Adjust seasoning to taste.
Follow steps 4 and 5 in the conventional method.
Recipe yields approximately 8 servings. Actual number of servings will depend on your preferred portion sizes and the cooking method.To calculate the weight of one serving, prepare the recipe as instructed. Weigh the finished recipe, then divide the weight of the finished recipe by 8. Result will be the weight of one serving.Nutritional values shown are guidelines only. They are for 1 serving using the ingredients listed. Actual macros may vary slightly depending on product brand and types of ingredients used.All recipes have been tested using all of the cooking methods included by various recipe testers.This recipe has also been shared to Diet Doctor for inclusion in their 2021 Holidays recipes and Members eMag.Store in an airtight container in the fridge for up to 4 days. Alternatively store in an airtight container and freeze.This recipe card instructions contains the most basic of steps and list of ingredients. If you have any queries, questions or are unsure of substitutions please scroll up to the blog post for more information.