This Low Carb tomato bisque comes out of the slow cooker thick and creamy, with no flour, no roux, and about 9 grams of net carb a bowl. It is everything canned tomato soup pretends to be, minus the 8 grams of added sugar a serving that sent me looking for my own version. Make a big pot, and it freezes beautifully if you hold the cream back until you reheat.
I love making soups in the winter. They are full of flavor and will keep you warm on a cold night. As much as I cook from scratch I don't ever start soups or marinara sauces with fresh tomatoes. I feel there has to be a line drawn somewhere in the sand to the amount of time you spend in the kitchen and for that reason I always start with canned diced tomatoes. They are picked at the peak of freshness and canned. This recipe is one of my favorites due to its simplicity. You just let your slow cooker do all the work while you are at the office all day and then puree it when you get home.
When you look at soups in the grocery store it is hard to find any that are even close to being Low Carb. I saw a can of tomato soup and figured that it might be low carb, but once I read that it was full of sugar I couldn't believe it! Why do so many things have sugar when they don't need it? In my opinion Tomato soup should be creamy, hearty, full of flavor, and above all not sweet. That is why I have brought this recipe to you today. Simply make up this easy recipe and keep it in your freezer for those days when you just want a bowl of soup almost as easy as popping open a can of Campbell's.
A low carb tomato bisque, no flour and no added sugar
A classic bisque gets its body from a flour roux or even a little rice. This one skips all of that. Once the vegetables cook down soft, an immersion blender purees them into a thick base, and the cream and parmesan finish the job, so the soup is rich and naturally gluten-free. The bigger win is what is not in it. A half-cup serving of canned tomato soup can carry around 8 grams of added sugar, listed fourth on the ingredient label. Tomatoes are sweet enough on their own, so there is no sugar in this pot at all.
Is tomato bisque really low carb?
Here is the honest answer most keto sites skip: tomato bisque is lower in carbs than the canned stuff, but it is not a zero-carb food. Tomatoes, onion, and celery all bring natural sugar, so a generous bowl lands around 9 grams of net carb. That fits most Low Carb and Atkins days, and it stays gentle for a diabetic plan in a sensible portion. If you want it lower, a couple of small tweaks help:
- Use more broth and one fewer can of tomatoes for a thinner, lighter bowl.
- Cut back the onion, the second-biggest carb source after the tomatoes.
The cream and cheese add almost no carbs, so the tomatoes are the dial to turn.
Make a big batch and freeze it right
This is the soup I make a double pot of, because it freezes better than almost anything. The trick is to freeze it before the dairy goes in. Cream and parmesan can break into a grainy mess once they are frozen and reheated, so I puree the tomato base, freeze that, and stir the cream and parmesan in fresh when I warm a batch up. Reheat it gently, since a hard boil can split the cream too. It keeps about 4 days in the fridge or three months in the freezer, ready for a night when a bowl of soup is all you want. A slice of crustless pizza or a handful of walnuts turns it into a full Low Carb lunch, and there are more Low Carb lunch recipes where this came from.
Sources:
USDA FoodData Central, nutrient reference for canned tomatoes, heavy cream, and parmesan
Campbell's Company, condensed tomato soup nutrition, added sugar reference
Sugarfreechic test kitchen, low-carb slow-cooker bisque notes
