Preheat your oven to 425°F (220°C). Cut the cauliflower into florets, season generously with kosher salt and black pepper, and drizzle with extra virgin olive oil. Arrange the florets on a baking sheet, ensuring they are in a single layer. Roast for about 45 minutes, turning halfway through, until the cauliflower is golden brown and tender.

While the cauliflower is roasting, heat a splash of olive oil in a large pot over medium heat. Add the chopped onion and cook for about 7 minutes, stirring occasionally until it becomes translucent and fragrant. Toss in the chopped garlic and remaining spices—cumin, paprika, sumac, and turmeric. Stir for 1 minute until the spices bloom.

Add about 3/4 of the roasted cauliflower to the pot with the sautéed aromatics. Pour in the vegetable broth and water, stirring gently to combine. Bring the mixture to a rolling boil, then reduce the heat to a simmer. Cook for 5-7 minutes.

Using an immersion blender, carefully blend the soup to your desired consistency—smooth and creamy is ideal. If using a regular blender, let it cool slightly before blending to avoid splattering.

Stir in the whole milk or your choice of unsweetened plant-based milk, along with the lemon juice. Incorporate the reserved roasted cauliflower, allowing its pieces to stay intact. Heat through and adjust seasoning with salt and pepper.

Ladle the creamy Mediterranean Cauliflower Soup into bowls and finish with a squeeze of lemon. Pair this dish with warm pita bread or a crisp Greek salad.