Preheat the oven to 204 degrees celsius. Coat a baking pan with olive oil and place the eggplant, tomatoes and pepper on it after cutting it into half. Eggplant and peppers need to be placed flat side down. Tomatoes can be kept flat side up.
Garlic can be cut into half across and wrapped in foil with a teaspoon of olive oil, salt and pepper.
Bake until the veggies are roasted for about 40 minutes. Place the peppers in a zip lock and let it sweat. (This makes it easy to peel the skin off.)
Let it all cool, then peel off the skin from peppers. Roughly chop the tomatoes and peppers.
In a soup pan, add one tablespoon oil. Then add the onions and cook until its pink in colour.
Add the pepper flakes, follow it up with the chopped tomatoes and peppers. Squeeze out the garlic from its skin and add it.
Scrape out the flesh from the eggplant and discard the skin. Add it to the soup along with 6 cups of water or stock. Also add the basil leaves.
Season per taste. Let it come to a boil and cook for 10-15 minutes. Then take it off the heat and once its cool enough puree it in batches.
Heat at the time of serving and serve with some grated cheese on top.