Wash the black lentils. I do this by placing the lentils in a pot and covering them with water. I stir the lentils with my hand, and the water will turn cloudy. Discard the water. Fill and repeat until the water runs clear. Then, set them aside.
Peel and chop the onion, ginger, garlic, and turmeric.
In a large pot, add the olive oil over medium heat. Add the onion, garlic, and turmeric to the pot and sauté for about 10 minutes. Then, add the celery and stir well.
Add the cumin, turmeric, smoked paprika, oregano, tomato paste, and vegetable broth. Stir until well incorporated.
Stir in the black lentils, and bring the mixture to a boil. Then, lower the heat to medium and cover the pot, and simmer for another 25-30 minutes, or until the lentils are tender but still hold their shape.
Add salt and pepper to taste.
Garnish with fresh cilantro or parsley and serve hot with a side of warm bread or rice. This stew can also be served with some avocado.