1. Roast the Cauliflower and Garlic:

1. Preheat your oven to 400°F (200°C).
2. Toss the cauliflower florets with 1 tablespoon of olive oil, salt, and pepper. Spread them on a baking sheet.
3. Slice the top off the head of garlic, drizzle with a little olive oil, and wrap it in foil. Place it on the baking sheet with the cauliflower.
4. Roast for 25-30 minutes, or until the cauliflower is tender and lightly browned, and the garlic is soft and caramelized.

2. Sauté the Vegetables:

1. In a large pot, heat the remaining 1 tablespoon of olive oil over medium heat.
2. Add the diced onion and celery, and sauté until softened, about 5 minutes.

3. Blend the Soup:

1. Squeeze the roasted garlic cloves out of their skins and add them to the pot along with the roasted cauliflower.
2. Pour in the chicken or vegetable broth and bring to a boil. Reduce heat and simmer for 10 minutes.
3. Use an immersion blender to puree the soup until smooth, or carefully blend it in batches in a countertop blender.

4. Add Cream and Cheese:

1. Stir in the heavy cream and shredded cheddar cheese.
2. Add smoked paprika and season with additional salt and pepper to taste.
3. Simmer gently over low heat until the cheese is fully melted and the soup is heated through (do not boil).

5. Serve:

1. Ladle the soup into bowls and garnish with croutons, a sprinkle of cheddar cheese, or fresh parsley.