Roasted Cauliflower Soup Recipe

Preheat the oven to 400°F.
Add chopped cauliflower to a large baking sheet, drizzle with two tablespoons of olive oil, season generously with salt, and toss until well coated. Transfer the baking sheet to the oven and allow the cauliflower to roast for 25-30 minutes until tender and lightly browned on the edges.
While the cauliflower is roasting, in a large pot or large saucepan, warm butter and remaining olive oil. Once melted, add leeks, onion, and garlic and cook for 5-7 minutes until vegetables are tender and slightly translucent.
Add mustard, nutmeg, and a pinch of salt, and stir to combine with the vegetable mixture. Then add potatoes and cover with broth, bring to a boil, cover with a lid, then reduce to a simmer and allow to cook for 15-20 minutes until the potatoes are tender and can be easily pierced with a fork. (You need just enough broth to cover the potatoes completely.)
Once the cauliflower has finished roasting and the potatoes are tender, add the cauliflower, parmesan cheese, and milk (just enough to cover the potatoes and cauliflower) to the pot and stir to combine.
Using an immersion blender or in batches using a bar blender, purée until smooth. Add additional milk as needed for desired texture and season to taste with salt and pepper as needed.
Once cooked, the soup can be served immediately into bowls or cooled completely and stored in an airtight container in the fridge for up to 5 days or in the freezer for up to 3 months.