In a medium saucepan, combine quinoa and vegetable broth. Bring to a boil, then reduce heat to low, cover, and simmer for 15 minutes or until quinoa is fluffy and liquid is absorbed.

In a large skillet, heat olive oil over medium heat. Add diced red bell pepper and cook for 3-4 minutes until softened.

Stir in black beans, corn, cumin, chili powder, and salt. Cook for another 5 minutes, mixing well.

Once quinoa is cooked, fluff with a fork and mix it into the skillet with the vegetable mixture. Stir in lime juice.

Take a lettuce leaf and fill it with the quinoa and black bean mixture. Top with sliced avocado, chopped cilantro, and salsa.

Repeat with remaining lettuce leaves and filling. Serve immediately.