Lentil Soup with Franankfurters

This German lentil soup is the kind of stick-to-your-ribs bowl you’d find in a Bavarian kitchen on a cold afternoon. Lentils simmer with bacon, leek, carrot, and celery until soft, then get thickened with a browned flour roux that adds a toasty, nutty depth most lentil soups don’t have.

The roux is what separates this from a basic lentil soup. You sauté onion in oil, sprinkle flour over it, and stir constantly until the flour turns light brown. Then you whisk in hot soup to temper the mixture before adding it back to the pot. It sounds fussy but takes five minutes and transforms the broth from thin to velvety.

Vinegar stirred into the roux is the other signature German touch. That splash of acidity cuts through the richness of the bacon and sausage, keeping the soup bright and balanced.

Frankfurters sliced thin and dropped in at the end just need a few minutes to heat through. They add a smoky, salty bite in every spoonful.

Chef Tips

• Don’t burn the flour. Stir constantly and keep the heat moderate. Burnt flour tastes bitter and can’t be fixed.
• Whisk the hot soup into the roux gradually to avoid lumps. A wire whisk is better than a spoon here.
• Partially cover the pot during the first simmer. Fully covered and the soup boils over; uncovered and too much liquid evaporates.
• This soup thickens significantly as it sits. Add water or broth when reheating leftovers.

Variations

• Smoked sausage: Use sliced kielbasa or bratwurst instead of frankfurters for a meatier version.
• Vegetarian: Skip the bacon and frankfurters, use vegetable broth, and add smoked paprika for depth.