Ingredients:

2 tablespoons oil
3 pounds boneless, skinless chicken breasts, cut into 1 inch pieces
1 medium onion, chopped
1 teaspoon oregano
1 small jalapeno pepper, finely chopped
3 cloves garlic, minced
1 can (14 1/2 ounce) Mexican style diced tomatoes
1/4 teaspoon ground cumin

Directions: 

Heat oil in skillet. Cook chicken pieces until browned. Remove and drain. Place onion, green bell pepper, garlic and jalapeno pepper in skillet and saute until slightly cooked.

Add all ingredients to Crockpot and stir to combine. Cover and cook on Low 8 hours. Serve on flour tortillas.