Grandmother’s Tomato Potato Soup
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This vintage Tomato Potato Soup is a simple, old-fashioned, but timeless recipe that makes a hearty meal with mostly pantry ingredients. Perfect for chilly days, either as a chunky tomato potato soup or a creamy tomato soup with a quick blend.
Recipe Overview
A simple, old-fashioned soup made with pantry ingredients.
- Ready in about 20-25 minutes
- Made mostly from pantry staples
- Mild, creamy, and comforting
- Delicious chunky or blended smooth
- A family recipe passed down through generations
Why I Love My Grandmother’s Soup
There are certain recipes that live far beyond the page - recipes made in quiet kitchens, shared during childhood illnesses, and remembered long after the cook is gone.
This tomato potato soup is my maternal grandmother's recipe, handwritten on a well-loved card that I still treasure. It was the soup she made whenever my mother was sick - gentle, nourishing, and deeply comforting.
Though my grandmother is no longer with us, this soup remains a favorite in our family. When I asked my mother if I could share it here on 31Daily, she was truly pleased - and that made it feel all the more meaningful to pass along.
What I love most about this soup is how uncomplicated it is - and how much comfort it brings with very little effort. I also love that it can be served two ways. My husband and mom prefer the chunky version, while I tend to love it pureed smooth and creamy - though I would never turn down either bowl.
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Ingredients
Made with basic pantry staples, this soup is as simple as it is comforting.
- Butter - for richness and flavor
- Onion - softens into the broth
- Garlic - just enough warmth
- Potatoes - russet or gold, both work beautifully
- Canned tomatoes - the heart of the soup
- Baking soda - a traditional touch (see note below)
- Evaporated milk - creamy without heaviness
If you love keeping a stocked pantry, be sure to see our guide on How to Reset Your Pantry, or check out our Sunday Edit No. 2 | The Pantry Reset for some of my favorite pantry resources.
Why This Recipe Uses Baking Soda
You may notice an unexpected ingredient in this soup: baking soda. While it isn't commonly used in many modern tomato soup recipes, it was a traditional technique used by home cooks for generations - especially in creamy tomato-based soups.
Tomatoes are naturally acidic, and baking soda helps neutralize that acidity. This creates a milder, smoother flavor and helps prevent dairy from curdling when milk is added.
You'll notice a bit of foaming when the baking soda is stirred in - that's completely normal and simply means it's doing its job. The result is a gentler, creamier soup that's easy to digest and wonderfully comforting - especially when you're not feeling your best.
How to Make this Tomato Potato Soup
This soup comes together quickly in one pot and requires very little hands-on time.
- Step 1: Sauté the onion. Melt the butter in a soup pot or Dutch oven over medium heat. Add the chopped onion and cook until softened and translucent, about 4-5 minutes. Stir in the minced garlic and cook for about 1 minute, just until fragrant.
- Step 2: Simmer the potatoes. Add the cubed potatoes and water to the pot. Bring to a gentle boil, then reduce the heat and simmer until the potatoes are tender, about 15 minutes.
- Step 3: Add the tomatoes and baking soda. Stir in the canned tomatoes and baking soda. The mixture will foam slightly - this is normal and helps neutralize the tomatoes’ acidity. Simmer for 1-2 minutes.
- Step 4: Stir in the evaporated milk. Pour in the evaporated milk and stir gently. Cook just until the soup is heated through. Do not boil.
Cooking and Serving Hints:
- Chunky or smooth: This soup is wonderful both ways - leave it chunky or blend until creamy.
- About the baking soda: A little foaming is normal and helps mellow tomato acidity.
- Avoid boiling after milk is added: Gentle heat keeps the soup smooth and creamy.
For an easy hands-off version, you might also enjoy this slow cooker tomato soup.
Serving Suggestions
I love finishing each bowl with freshly cracked black pepper and a sprinkle of shredded Parmesan - simple, cozy, and deeply comforting. Serve with garlic bread, a classic pairing with grilled cheese sandwiches, or a side salad with fresh greens.
This soup can be enjoyed two ways:
- Chunky, just as my grandmother often served it
- Smooth and creamy, pureed with an immersion blender or high-speed blender
If you enjoy tomato-based soups, you may also like our classic creamy tomato soup, made rich and smooth with simple ingredients.
Recipe FAQs
This is a traditional method used in many older tomato soup recipes. Baking soda helps neutralize the natural acidity of tomatoes, creating a milder flavor and helping prevent dairy from curdling when milk is added. You may notice some foaming - that's completely normal.
You can, but the soup will taste slightly more acidic and the milk may be more likely to curdle. The small amount used here helps create a smoother, gentler soup - especially when served creamy.
Russet or Yukon Gold potatoes both work well. Russets soften more and help thicken the soup, while Yukon Golds hold their shape slightly better.
Yes - and both versions are delicious. Serve it chunky for a more rustic, old-fashioned feel, or puree the soup using an immersion blender or standard blender for a smooth, creamy texture.
You can, though canned tomatoes provide consistent flavor year-round. If using fresh tomatoes, peel and seed them first, and expect a slightly lighter flavor.
Store leftover soup in an airtight container in the refrigerator for up to 3 days. Reheat gently on the stovetop or in the microwave.
When tomatoes are in season, our fresh garden tomato soup is another reader favorite.
More Delicious Soup Recipes
Looking for other recipes like this? Try these:
- 35 Winter Soup Recipes
- Crock Pot Chicken and Rice Soup
- New Year’s Day Black Eyed Peas Soup
- Christmas Soup Recipes
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Grandma’s Tomato Potato Soup Recipe
Equipment
Ingredients
- 2 tablespoons butter
- 1/2 onion chopped, about 1/2-3/4 cup
- 2 garlic cloves minced
- 12 ounces water
- 1 potato peeled and cubed (1-2 cups)
- 1 (15-oz) can diced tomatoes undrained
- 1/2 teaspoon baking soda
- 12 ounces evaporated milk
- salt and pepper to taste
Instructions
- Melt butter in a soup pot or Dutch Oven. Then, sauté the onion until softened. Add the garlic and saute another minute.
- Into the pot, add the chopped potatoes and water. Bring to a boil,then reduce heat to a simmer and cook until the potatoes are softened, about 15 minutes.
- Stir in the tomatoes and baking soda and simmer for 1-2 minutes more. The baking soda will foam in the pot.
- Stir in the evaporated milk and cook until heated through. Season with salt and pepper to taste. You can serve the soup chunky or pureed in a high-speed blender until smooth and creamy. Serve hot.
Serving
- You can serve the soup chunky or for a smooth consistency, puree using an immersion blender or standard blender, until smooth and creamy. I like to serve with freshly cracked pepper on top and shredded Parmesan for the ultimate comfort food!
Notes
- Baking soda: The baking soda may cause the soup to foam briefly - this is normal and helps neutralize tomato acidity.
- Do not boil after adding milk: Once the evaporated milk is added, keep the heat gentle to maintain a smooth, creamy texture.
- Chunky or smooth: This soup can be served just as it is, or blended until smooth using an immersion blender or standard blender.
- Potato choice: Russet potatoes create a slightly thicker soup, while Yukon Gold potatoes hold their shape a bit more.
- Season at the end: Salt and pepper are best added after the soup is finished, as tomatoes can concentrate flavors while simmering.
- Serving suggestion: Delicious served with crusty bread, toast, or a simple grilled cheese sandwich.
- Storing the soup: Refrigerate the soup in an airtight container for up to 3 days. Reheat gently on the stovetop.
Nutritional information is only an estimate. The accuracy of the nutritional information for any recipe on this site is not guaranteed.
This soup recipe has been in my family for generations. And yet, all these decades later, it’s still loved, made, and enjoyed. I especially love making this quick pot of soup on chilly days and enjoying it for hearty lunches!