In a large pot, heat a generous splash of olive oil over medium heat. Add sliced onions along with a pinch of salt, stirring occasionally. Sauté for 15-20 minutes, until the onions are golden brown and caramelized.

Once the onions are beautifully caramelized, add minced garlic, ground cumin, and smoked paprika to the pot. Stir everything together for 1-2 minutes.

Next, add diced carrots to the pot, stirring them in with the onion and spice mixture. Cook for another 5 minutes.

Now incorporate rinsed red lentils, vegetable broth, and diced tomatoes. Stir well to combine, and bring the mixture to a boil.

Once boiling, reduce the heat to low and cover the pot. Let the soup simmer for about 20 minutes, or until the lentils are tender.

After simmering, remove the pot from heat. Use an immersion blender to puree the soup to your preferred consistency.

Finally, stir in fresh lemon juice and adjust seasoning with salt and pepper to taste. Garnish with freshly chopped parsley or cilantro before serving.