Linsensuppe Mit Frankfurter (Lentil Soup With Franks)

Linsensuppe mit Frankfurter is German comfort food at its most honest. Lentils simmer with bacon, leek, carrot, and celery until they break down into a thick, earthy base. The real trick is the browned flour roux made separately in a frypan. Cooking that flour until it turns light brown (without burning it, and yes, you need to babysit it) gives the soup a toasty, almost nutty backbone that sets it apart from other lentil soups.

The splash of vinegar stirred into the roux before it joins the pot is not optional. That acidity cuts through the richness of the bacon and lentils, brightening the whole bowl. It’s a classic German technique you’ll find in kitchens from Bavaria to Berlin.

Sliced frankfurters go in near the end, just long enough to heat through. They add a salty, smoky bite in every spoonful without overcooking into mush.

Pro Tips

• Stir the flour constantly while browning. Walk away for 30 seconds and it goes from golden to burnt
• Whisk the hot lentil broth into the roux gradually. Dumping it all at once creates lumps that won’t dissolve
• Use a good quality vinegar here. White wine vinegar or apple cider vinegar both work well
• The soup thickens considerably as it sits. Add water or broth when reheating leftovers

Variations

• Swap frankfurters for smoked kielbasa or bratwurst slices for a different smoky character
• Stir in a spoonful of German mustard at the table for extra bite
• Add diced potato with the lentils for an even heartier version