In a large pot, sauté the onion, carrots, and mushrooms with a splash of vegetable broth over medium heat until the vegetables have softened.
Stir in the minced garlic, ground cumin, smoked paprika, sea salt, and black pepper, cooking for one minute until the spices are fragrant.
Add the dry red lentils and the remaining vegetable broth to the pot, stirring to combine.
Bring the mixture to a boil, then immediately reduce the heat to low and simmer for 15 to 20 minutes until the lentils are tender and have broken down slightly.
Stir in the nutritional yeast and hemp seeds to thicken the stew and provide a savory, nutty depth.
Fold in the fresh spinach and lemon juice, stirring constantly until the greens are just wilted.
Ladle the stew into a bowl and serve immediately while hot.