Caramelized Onion Red Lentil Soup (Print)

Rich, comforting soup with deeply caramelized onions and hearty red lentils, fragrant spices, perfect for any meal.

# Ingredient List:

→ Vegetables

01 - 3 large yellow onions, thinly sliced
02 - 2 cloves garlic, minced
03 - 2 medium carrots, diced
04 - 1 stalk celery, diced

→ Lentils & Staples

05 - 1 cup dried red lentils, rinsed
06 - 6 cups vegetable broth

→ Spices & Seasonings

07 - 2 tbsp olive oil
08 - 1 bay leaf
09 - 1 tsp ground cumin
10 - 1/2 tsp smoked paprika
11 - 1/4 tsp ground black pepper
12 - 1/2 tsp dried thyme
13 - 1–1.5 tsp salt, to taste

→ Garnish (optional)

14 - Chopped fresh parsley
15 - Lemon wedges

# How-To Steps:

01 - Heat olive oil in a large soup pot over medium-low heat. Add sliced onions with a pinch of salt. Cook, stirring occasionally, for 20–25 minutes until onions are deeply golden and caramelized.
02 - Add minced garlic, diced carrots, and celery to the pot. Sauté for 3–4 minutes until vegetables are slightly softened.
03 - Stir in ground cumin, smoked paprika, black pepper, dried thyme, and bay leaf. Cook for 1 minute until spices become fragrant.
04 - Add rinsed red lentils and vegetable broth. Bring to a boil, then reduce heat to maintain a gentle simmer. Cook uncovered for 15–20 minutes until lentils and vegetables are completely tender.
05 - Remove and discard bay leaf. Use an immersion blender to partially or fully blend the soup according to preferred consistency.
06 - Taste soup and adjust salt and pepper as needed. Serve hot, garnished with fresh parsley and lemon wedges.

# Expert Suggestions:

01 -
  • The depth of flavor from properly caramelized onions makes this taste like it simmered all day even though it comes together in under an hour
  • Red lentils practically dissolve into the soup creating this incredibly creamy texture without any dairy
  • Something magical happens when smoked paprika meets sweet onions in this recipe
02 -
  • Rushing the caramelization step is the biggest mistake you can make with this recipe because those deep sweet onions are the entire foundation of flavor
  • Red lentils cook faster than other varieties so do not walk away once they start simmering or you might end up with something closer to a puree than a soup
  • The soup continues thickening as it sits so if you prefer it thinner add a splash more broth when reheating leftovers
03 -
  • Slice your onions as evenly as possible so they caramelize at the same rate instead of some burning while others stay raw
  • Use a pot with a wide bottom rather than a tall narrow one which helps the onions brown more evenly by giving them more surface area

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