In saute pan, heat olive oil over medium-high heat. Once hot, add onions and cook 2-3 minutes. Add garlic, cook for another minute and then add in cumin, salt, and pepper. Turn heat off.
Turn slow-cooker on high. Add onion mixture to bottom of slow-cooker and layer in corn, beans, and green chiles. Add chicken breasts on top and then pour enchilada sauce overtop of chicken.
Dollop cream cheese into a few dollops over top of chicken. Cover with lid and cook on high for 3-4 hours or until chicken is easily shreddable with a fork.
Remove chicken from crockpot and shred with two forks. Once shredded, add back to crockpot and mix.
Layer on pieces of corn tortilla and then cover with cheese. Put lid back on and let cook on LOW for 45 more minutes.
Serve with sour cream, cilantro, jalapenos and over rice if desired.