For salsa, combine all ingredients in a small bowl and toss to coat. Set aside.
Rinse lentils with cold water and sift through, making sure there are no small stones mixed in.
Bring a pot of salted water to a boil. Add lentils, and cook for 20 minutes or until tender but still slightly al-dente. Drain.
Heat a few splashes of olive oil in large skillet over medium-high heat. Add onion, garlic, and chili and cook until onion begins to soften, 3 to 4 minutes.
Add lentils and paprika and cook until coated and heated through.
Spoon lentil mixture onto warmed tortillas. Top with salsa, lettuce, and mozzarella cheese.
