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Crock Pot Lentil Soup Recipe
Ash Tyrrell

Crock Pot Lentil Soup Recipe

I still remember the first time I let my slow cooker do all the work for dinner and walked into a kitchen that smelled like a cozy little Italian café. That's exactly what happened the day I made this crock pot lentil soup.
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Prep Time 10 minutes
Cook Time 6 hours
Servings: 6
Ingredients Method Notes

Ingredients
  

  • 2 tablespoons olive oil – helps soften the veggies and builds the flavor base
  • 1 medium yellow onion diced – adds natural sweetness once it's browned
  • 4 medium carrots diced – brings color and a subtle earthy sweetness
  • 3 stalks celery sliced – rounds out the classic soup flavor trio
  • 1 ½ teaspoons Italian seasoning – an easy way to layer in herby depth
  • 1 teaspoon kosher salt – brings all the other flavors to life
  • 1 teaspoon smoked paprika – gives the broth a warm smoky note
  • ½ teaspoon black pepper – for a little gentle heat
  • 4 cloves garlic minced – use fresh, not jarred, for the best aroma
  • 1 ½ cups green or brown lentils – skip red lentils they turn mushy over a long cook
  • 1 can 15 oz fire-roasted diced tomatoes – adds a subtle charred sweetness
  • 1 can 15 oz crushed tomatoes – thickens the broth naturally
  • 4 cups low-sodium vegetable broth – keeps you in control of the saltiness
  • Parmesan rind optional – a small addition that adds big savory flavor
  • 1 tablespoon red wine vinegar – brightens the whole pot right before serving
  • ½ teaspoon granulated sugar – balances the acidity from the tomatoes
  • Fresh parsley and Parmesan for serving – adds freshness and a savory finish

Method
 

  1. Warm the olive oil in a large skillet over medium-high heat, then add the diced onion. Let it cook until soft and lightly golden, about 8 minutes, stirring now and then. Stir in the carrots, celery, and spices, and cook for another 2 minutes before adding the garlic for just 30 seconds.
  2. Scoop the sautéed vegetable mixture into your slow cooker. Add the lentils, both cans of tomatoes, the vegetable broth, and the Parmesan rind if you're using one. Give everything a good stir so the lentils are fully submerged in the liquid.
  3. Cover the slow cooker and cook on low for 6 to 8 hours or on high for 3 to 4 hours. You'll know it's ready when the lentils are tender but still hold their shape rather than turning to mush.
  4. Remove the Parmesan rind, then stir in the red wine vinegar and sugar to balance the flavors. Taste and adjust the seasoning, thinning with a splash of broth if the soup feels too thick, then ladle it into bowls.

Notes

  • I always rinse my lentils first to wash away any dust or debris hiding in the bag.
  • I've found French green lentils hold their shape best, so I reach for those over regular green lentils when I can.
  • I like to save my Parmesan rinds in the freezer specifically for soups like this one.
  • I add the vinegar at the very end instead of during cooking, since the flavor stays brighter that way.
  • If my soup thickens too much overnight, I just stir in a little extra broth while reheating.