Heat olive oil in Dutch oven over medium heat. Add onion, red pepper, salt and pepper. Sauté for 3-4 minutes, stirring frequently.
Add jalapeño and garlic; stir to combine.
Add 2 Tablespoons chili powder, 1 Tablespoon ground cumin, paprika, diced tomatoes, tomato paste and water; stir to combine. Bring to a low boil over medium-high heat.
Once boiling, add lentils and reduce heat to medium-low. Gently simmer uncovered for 15 minutes, or until lentils are mostly tender. If necessary, add more water if the mixture is looking too dry.
Add black beans, corn, remaining 1 Tablespoon chili powder and remaining 1 Tablespoon cumin. Stir to combine. Bring to a simmer over medium heat. Cover and reduce heat to medium-low. Gently simmer for 20 to 25 minutes, or until onions and peppers are tender.
Taste and adjust seasonings as needed, adding more chili powder or cumin for smokiness, salt for saltiness, or a little brown sugar to balance the heat and draw out the other flavors. Serve as is, or garnished with shredded cheese, fresh jalapeño, sliced green onion, diced tomatoes, etc.
Store leftovers in the refrigerator up to 4 days and in the freezer up to 1 month. Yield: 6 servings. (See Tip 3)