Warm a large soup pot over medium heat. Add the oil and onion. Saute until tender and translucent, about 4-5 minutes. Add the jalapeno and garlic and sauté until fragrant, about 1 minute.
Add the cumin and chili powder and sauté for 1 minute.
Add the remaining ingredients except the toppings. Raise the heat to high and bring to a boil. Lower heat to a simmer, cover and cook until the lentils are soft, about 20-25 minutes.
Taste for seasoning and serve with desired toppings.
Notes
Feel free to make this spicy by adding more jalapenos, a Serrano pepper, or cayenne. There are other toppings that would work as well, such as chopped onion, more fresh cilantro, or sour cream if you make it hot.