Heat olive oil in a skillet over medium heat. Add diced onion and minced garlic, sauté until translucent.

Stir in cooked lentils, bell pepper, corn, cumin, chili powder, salt, and pepper. Cook for about 5-7 minutes until heated through.

Warm corn tortillas in a separate skillet or microwave.

Fill each tortilla with the lentil mixture, then top with shredded lettuce, diced tomato, avocado slices, and chopped cilantro.

Serve with lime wedges on the side.