Wash and cut your tomatoes in half and add to a baking dish.
Add in your sliced red onion, garlic cloves, salt, oregano, basil, black pepper, and olive oil. Mix well.
Bake at 400°F for 20 minutes.
Remove from oven and carefully add to a blender. Add in your chicken bouillon cube, heavy cream, water, and blend until smooth. You can strain the mixture for a smoother texture.
Transfer your soup to a pot and add in your butter, sugar and cornstarch slurry and cook on medium heat for 10 minutes.
Drizzle some cream over your soup and serve hot with a grilled cheese sandwich.