Preheat the oven to 400 degrees F. Line a baking sheet with parchment paper.

Cook the veggies: Add cauliflower florets to the pan, drizzle with 1-2 tablespoons of olive oil and season generously with salt and pepper; toss to combine. For the garlic: peel and discard the outer papery layers of the whole garlic head. Leave the skins intact of the individual cloves. Using a sharp knife, cut ¼ inch off from the top of the cloves so that the individual cloves of garlic are exposed. Place garlic in a medium piece of foil and drizzle the top of the garlic with olive oil then loosely wrap in the foil and place on the pan with the cauliflower. Roast cauliflower and garlic for 30-35 minutes, flipping halfway through, until cauliflower is nice and golden and caramelized.

Cook the onion: While the cauliflower is cooking, add 1 tablespoon olive oil to a pot and place over medium heat. Once oil is hot, add in diced onion and saute for 5-8 minutes until onion is translucent.

Blend the soup: In a large blender add the onion, roasted cauliflower, roasted garlic, broth, salt and pepper. Blend until smooth, about 1 minute, then add back to the pot and place over medium heat. Tip for the garlic: allow it to cool enough to touch then simply squeeze out the roasted garlic from the skin.

Finish it off: Bring soup to a light simmer, then stir in the cheddar cheese. Simmer for 10-15 minutes, taste and adjust seasonings as necessary. Garnish with green onion and extra grated sharp cheddar cheese. Serve with crusty toasted sourdough or your favorite bread of choice.