Prepare the Lentils: Rinse the red, green, and brown lentils under cold water and set aside.
Sauté the Aromatics: Heat olive oil in a large pot over medium heat. Add the diced onion, minced garlic, carrot, and celery. Sauté for 5 minutes until softened.
Add the Spices: Stir in garam masala and cayenne pepper. Cook for 1 minute to release their aroma.
Incorporate Tomato Paste and Tomatoes: Add the tomato paste and stir well. Then add the diced tomatoes, mixing to combine.
Add Lentils and Stock: Pour in the vegetable stock or chicken stock and add the lentils and bay leaves. Bring to a boil, then reduce heat to medium and simmer for 30-35 minutes until the lentils are tender.
Season and Finish: Remove bay leaves, add a dash of balsamic vinegar, and season with salt and black pepper to taste.
Serve and Garnish: Ladle the soup into bowls, garnish with fresh coriander, and enjoy!
