Preheat oven to 400°F.
Peel the garlic cloves and quarter the onions. Chop cauliflower and sweet potato into bite-sized chunks. Combine garlic, onion, cauliflower and sweet potatoes - drizzle with 2 tablespoons of coconut oil and toss to coat. Spread out on baking sheet and sprinkle with sea salt. Roast until everything is golden, approx. 30-40 minutes.
Let veggies cool and then add to a blender along with broth, milk and lemon juice. Do in batches if you have a small blender. Adjust liquid ratio based on how thick you want your soup. Taste and adjust the seasoning, if necessary - add more sea salt, another squeeze of lemon or a dash of hot sauce if you are feeling spicy.
Transfer to a pot to reheat. Drizzle with olive oil before serving. Goodbye sickness, hello immunity boost!