Rub chicken breasts with salt, pepper, chili powder, and cumin. Place in the crockpot.
Mince one onion to yield 2/3 cup. Place in a small bowl and microwave for one minute. Transfer to crockpot.
Add salsa to crockpot and mix with onions. Put cream cheese on top of everything.
Cook on low for 2 hours or on high for 1 hour (cooking time may vary depending on your crockpot. It is done when the chicken registers 165 degrees).
Take the chicken out and let it rest at least 5 minutes. Then, shred on a plate with 2 forks.
Mix the salsa and cream cheese together well (I use a whisk—it will take a little bit but just keep stirring and they will combine!) Then add chicken back in and stir.
CHEESE OPTION 1: Portion out on top of chips. Top with cheese, then microwave for 20 seconds or until cheese has melted.
CHEESE OPTION 2: Add cheddar cheese to the crockpot and cover. Cook for 20 more minutes or until cheese is melted.
Serve on top of tortilla chips with cilantro, green onions, and avocado!