Tomato Potato Soup (番茄土豆汤)

This simple tomato potato soup is a summer staple, with just 5 ingredients (plus water). It’s a light snack or side dish that replenishes your body with fluids and salt on those sweat-inducing hot days! 

A Simple Childhood Soup from Shanghai

In our cookbook, I shared stories of my childhood encounters with food while living with my grandmother in Shanghai. This soup comes from my memories of that time. 

We lived in close quarters in a multi-family building, with every family doing their cooking in the shared walkway where the only sink in the building sat. Not only did we all know each other’s business, we also knew what everyone was cooking for the day. 

In the summer, this soup was literally on every family’s table multiple times a week.

Soups that the Shanghainese cook in the summer are always simple and quick. It rotated between this tomato potato soup, tomato egg drop soup, seaweed egg drop soup, and a soup of potatoes and preserved vegetables (咸菜土豆汤). 

Back then, we didn’t have grocery stores or full pantries to work with. Many of our soups were made with water (there were no boxes or cans of pre-made stock!), and we cooked with what we had and what was in season. Tomatoes and potatoes were always key summer produce items.

We recently posted an article on how to create umami with vegan ingredients, and tomatoes are one of the main items on the list. This soup really demonstrates the umami power of tomato! 

With no spices other than salt, this soup shines with just that tomato and the light aroma from the potato. I think it’s pretty tasty, for having so few ingredients! While it may sound simple, don’t knock it until you try it. 

Soup in Summer?

Summer in Shanghai has some extreme heat, and I lived through a time in which there was no air conditioning. It may seem ridiculous to make hot soup in such an environment. 

But then again, TCM (traditional Chinese medicine) tells you to eat a lot of ginger in the summer, which is a warming ingredient—also seemingly counterintuitive. However, in the summer, we’re eating a lot of cooling ingredients—watermelon, cucumber, and other fruits, not to mention cold drinks or desserts, and ginger is recommended to balance those out. 

A warm soup may not be so crazy after all. Tomatoes are a “cooling” ingredient according to TCM, expelling heat from the body, while potatoes have a neutral constitution and provide energy. That said, you can serve this soup hot or at room temperature. 

Furthermore, in the heat of summer, your body loses a lot of fluids and salt from sweating. You can be generous with the salt in this soup to set off the flavor of the tomatoes and help replenish those electrolytes, and the thin broth will help you rehydrate. 

Tomato potato soup tastes best when made with fresh, in-season summer tomatoes. The tomatoes in our garden are producing fruit, and the potato plants are ready for digging, so we know we’ll be making it often in the coming weeks. 

Tomato Potato Soup Recipe Instructions

Prepare the tomatoes and potatoes. If you’re not cooking the soup right away, keep the potatoes in a bowl of cold water to prevent them from oxidizing (turning brown). 

Heat oil in a medium soup pot over medium-high heat, and add the tomatoes. Cook for 3-5 minutes, until tomatoes have softened and broken down a bit. 

Add the water and potato, and bring to a boil over high heat.

Once boiling, cover, reduce the heat to medium, and cook for 15 minutes.

Finally, add the scallion and salt to taste (don’t be afraid to be generous with the salt). 

Serve hot or at room temperature!