Season the chicken breasts with salt and pepper and cook for about 6 minutes. Flip the chicken and cook the second side for about 6 minutes more, or until chicken is cooked through.
Allow chicken to rest for 5 minutes.
Cut the chicken into bite-sized cubes.
Place the avocado and lemon juice into a large mixing bowl. Use a fork to mash the avocado until it reaches a creamy consistency. Add the jalapeno, garlic, cilantro, and cumin. Season well with salt and pepper. Stir to combine. Mix in the cubed chicken.
Place 1-2 tablespoons of the guacamole chicken in the center of a Boston lettuce leaf. Crumble one tortilla chip over the top. Repeat until all the guacamole chicken mixture is used. Serve immediately.
Recipe by Jen Elizabeth's Journals at https://jenelizabethsjournals.com/2012/08/01/guacamole-chicken-lettuce-wraps/