In large pot, heat oil and sauté onion, jalapeño (if using), ginger, garlic and curry powder. Combine well and cook until aromatic.
Add tomatoes and cook for 10 minutes on medium-high heat.
Stir in water and drained lentils and bring to boil. Reduce heat to low and cook for approximately 30 minutes or until lentils are soft enough to mash (adding more water if necessary to extend the cooking time).
Add salt and spinach cook until wilted, 1-2 minutes.
Serve over warm brown rice and garnish with cilantro, optional.
