Melt the coconut oil in a large saucepan over medium heat.
Add the leek and a pinch of salt and cook gently for 10 minutes or until softened and golden.
Add the stock and most of the cauliflower florets (reserve 1 cup of small florets for garnish).
Bring to the boil, then reduce the heat and simmer, covered, for 20 minutes or until the cauliflower is tender.
Add Brazil nuts, then blend with a stick blender until smooth and creamy.
Season with salt and pepper to taste.
To make the topping, melt the coconut oil in a frying pan over medium-high heat.
Chop the reserved cauliflower florets into a rough crumb, add to the pan and cook until just crunchy.
Top each bowl of soup with the crunchy cauliflower, chopped Brazil nuts and parsley.