Rinse the dry green lentils under cold water until the water runs clear.
Press the extra firm tofu to remove excess moisture and cut it into small half-inch cubes.
In a large pot, sauté the yellow onion, carrots, and celery with a splash of vegetable broth over medium heat until softened.
Stir in the garlic, ground cumin, and smoked paprika, cooking for one minute until fragrant.
Pour in the dry green lentils, tofu cubes, and the remaining vegetable broth.
Bring the mixture to a boil, then reduce heat to low and simmer, covered, for 20 to 25 minutes until the lentils are tender.
Stir in the nutritional yeast and baby spinach, allowing the leaves to wilt into the hot stew.
Season with sea salt and black pepper before serving in deep bowls.