Season the chicken breasts with salt, pepper and garlic powder and place in crockpot. Pour salsa over top of chicken. Cover and cook on LOW for 6 hours or HIGH for 4 hours. 

Use a hand mixter to finely shred chicken. Stir in half the green onions, the second jar of salsa (I used a corn and black bean salsa for the 2nd jar), and the ranch dressing. 

Preheat oven to 350F. 

Fit a tortilla into the well of a standard sized muffin pan.  Spoon 2/3 full with chicken , top with approximately 2 tablespoons of shredded cheese. Repeat with remaining tortillas.

Bake in preheated oven for 15 minutes. Remove from oven and top with sour cream, jalapeño slice, green onion, and chopped tomato. Serve immediately.