In a large pot, heat the oil over medium heat. Add the onion, garlic, and pinch of salt. Saute for 4 to 5 minutes or until the onion is softened.
Add the turmeric, cumin, coriander, smoked paprika, and cayenne pepper. Stir to mix in with the onions and saute for about 1 minute or until fragrant.
Add the diced tomatoes, coconut milk, red lentils, vegetable broth, salt, and pepper. Stir to combine. Increase the heat to high until it reaches a low boil. Once at a boil, reduce the heat to medium-high and simmer (uncovered) for 18 to 22 minutes or until the lentils are tender (stirring occasionally).
Turn off the heat and immediately stir in the spinach until wilted. Add the juice of 1 lime. Add more salt and pepper if needed.
Serve and enjoy!