Take a skillet, heat olive oil in it, and add chopped onion and carrots, and oregano. Saute them over medium heat till the onion becomes translucent.
Add the roughly sliced tomatoes, salt, and pepper. Give it a stir, and add water.
Now cover the skillet, and let it simmer on medium heat for 10-15 minutes till all the ingredients have become mushy.
Transfer the mixture to a blender and blitz thoroughly. Then strain the mixture properly to get a smooth soup.
Transfer it to the skillet, switch on the flame on low heat, and add heavy cream, and basil leaves.
Make final adjustments to the soup by adding more water, salt, or pepper, and let it simmer for a minute.
Now pour the soup into a bowl, and finish it with basil leaves and heavy cream on top before serving.