Heat 2 tablespoons of olive oil in a large pot over medium heat. Add finely chopped onion and minced garlic. Sauté for 3-4 minutes until onion is translucent.

Stir in diced carrot and diced celery, cooking for an additional 3 minutes.

Add 1 teaspoon each of cumin, coriander, turmeric, and paprika, along with a pinch of red-pepper flakes. Stir for about 1 minute.

Pour in 1 cup of lentils, 4 cups of vegetable broth, and 14-ounce can of crushed tomatoes. Stir to combine and bring to a gentle boil. Reduce heat to low and simmer for 15-20 minutes.

Once lentils are cooked, add juice of half a lemon and season with salt and pepper to taste.

Ladle soup into bowls and drizzle with extra olive oil. Garnish with chopped parsley or cilantro.