Cut up one large head of cauliflower into florets. Discard the stalk and leaves. Place on a parchment-lined baking sheet and sprinkle with a little salt and pepper. Roast at 400 degrees fahrenheit for 30 minutes, turning halfway.
Saute the carrots and cook the lentils while the cauliflower is roasting. Set both aside.
To a large pot, add: roasted cauliflower, almond milk, vegetable stock, nutritional yeast, soy sauce, garlic powder, onion powder, parsley, paprika, and thyme.
Warm up the soup a little on medium heat - you don't have to bring it to a simmer, but you want it warm to help it blend up better.
Blend 2 cups of the soup until creamy. Transfer back to pot. (Or use an immersion blender.)
Add in carrots and lentils. Bring to a simmer over medium heat.
Stir in the spinach and simmer for another minute, or until the spinach is wilted. Serve.