Add chicken pieces, taco seasoning and lime juice to a ziplock bag and shake well to combine.
Refrigerate while you make the white bean salsa, or for up to 8 hours.
For the Salsa:
To a food processor or blender add onion, jalapeño, cilantro, lime juice and salt. Pulse/blend until finely diced.
Remove contents to a bowl. Stir in white beans. Refrigerate.
Add a little olive oil to a skillet over medium high heat. Add chicken pieces and cook, turning once, until cooked through.
Allow chicken to rest for a few minutes before shredding it with two forks.
Spread a small handful of cheese into a single layer on a tortilla.
Add a handful of shredded chicken and 1/4 cup white bean salsa.
Sprinkle another small handful of cheese on top. Cook quesadilla on a clean skillet over medium heat, flipping once, until tortillas are golden and cheese is melted.
Serve warm with diced avocados and extra white bean salsa and sour cream, if desired.