Preheat oven to 200 ˚C. Prepare a baking dish.
Drizzle two tablespoons of olive oil over the cauliflower until lightly and evenly coated in oil in the baking dish. Arrange the cauliflower in a single layer and sprinkle with salt. Bake for 25-35 minutes, turning after 10-15 minutes.
In a pot, heat the remaining one tablespoon of olive oil over medium heat. Add the onion and a quarter teaspoon of salt. Cook, stirring occasionally, until the onion is soft and translucent.
Add the garlic and cook, stirring constantly, until fragrant, about 30 seconds. Then add the stock.
Reserve four of the nicest roasted cauliflower florets for garnish. Then transfer the remaining cauliflower to the pot. Bring the mixture to a simmer. Stir occasionally, for 20 minutes, to give the flavors time to blend.
Once the soup is cooked, remove the pot from the heat and let it cool for a few minutes. Then place the soup in a food processor with the cream and cheese. Blend well.
Add the butter, lemon juice and nutmeg and blend until smooth. Taste and adjust the salt and lemon juice as needed.
Fill bowls with the soup.
Top with one roasted cauliflower floret, bacon and chives for garnish.