The variations for tomato soups will differ as long as there are cooks who will take interest making this soup or there is always Campbell. Hot/Warm tomato soup is comforting in a cup to hold when you can feel the warmth on your fingers holding the cup.
When you see the hot steaming soup in a bowl the feeling is more comforting because the open bowl welcomes you to warm and fuzzy feelings of your childhood days when you slowly slurped the hot soup with a spoon from the bowl sitting in front of a television. Any way the soup signals comfort to all who have grown up with it. Considering that tomatoes are plenty available in summer and easily available in a can in any corner shop, it is one of the easiest things to cook.
And if you have a can of tomato paste, the easier it is.
For the novice,tomato soup is Tomatoes, water and salt in a pan and turn on the stove. You can use the 'sting finger' test to find out if the soup is hot/boiling/warm. Dip your finger in the soup !If the finger stings,it is hot. if the finger burns,it is boiling. You can continue to test with the “sting finger” method till you are happy with the temperature of the soup. It will be called tomato soup by any definition. Easier than boiling water, if you do not know when the water is boiled.
I did not grow up eating tomato soup because it was considered a fancy item and it was to be had in upscale restaurants in a pretty little white bowl which I didn't much like it then because It was simply hot.
Who would want to drink hot soup when one is staying a tropical country with temperatures steaming over 40 degrees C every day and the added humidity. And people would drink soup only if one sat in the Air conditioned part of the restaurant, where the A/C machines were blasting and the place had pretty little recessed lights – tomato soup was also the most common appetizer and the fastest to arrive on the table before the dinner arrived.
The first time I made tomato soup was when I was in the US and had nothing to eat at home. The ingredients were bought at the only available drug shop that stayed open late into the night.(Drug stores in the US like the CVS and Rite Aid sell more than prescription and on the counter medications) The extra ingredient to spruce up the tomato soup was a can of meat. spam - to be exact. Yes, you read that right.
Adding water, tomato paste, salt, garlic,meat and pressure-cooked to seal in the flavors,the tomato soup was ready to be savored with toasted bread.
Fast forward during the decade the tomato soup has taken on many dimensions,but I newly discovered that grated radish,and tomatoes from a can when browned in the pan quadruples the flavor along with grated garlic, ginger, green chilies,salt, water and pressure cooked. Slurp with a spoon,or Drink up – It soothes you in every way. I now know why it is comforting.
Note:Pressure-cooked soup seals the flavor in the cooker.It is as delicious as a day old soup.