Heat a large stock pot over medium heat. Add oil.
Saute carrot, onion, broccoli and garlic until starting to get soft, about 10 minutes.
Sprinkle in the flour and stir to combine with vegetables. Stir for about 1-2 minutes.
Add in broth and non-dairy milk. Stir to remove lumps.
Add nutritional yeast, salt and pepper. Stir.
Bring to a simmer and cook for about 30 minutes.
After 30 minutes, stir in lemon juice. Next you will puree only about 1/3 of the soup. If using an immersion blender, only puree partially and leave chunks of carrot and broccoli. If using a blender, let soup cool and then puree only 1/3 of the soup in the blender and return to the pot.
Taste and add additional salt and pepper as needed.