Crock Pot White Chicken Chili

1 Tbsp. olive oil
½ c. chopped onion
3 lb. boneless, skinless chicken breast, cut into small cubes
4 c. unsalted chicken stock
1-2 Poblano peppers, diced
2 (15.5 oz.) cans cannellini beans, drained and rinsed
2 (16 oz.) can navy beans, rinsed and drained
2 tsp. garlic powder
3 tsp. ground cumin
1 tsp. dried oregano leaves, crushed
1 tsp. dried cilantro leaves, crushed
¼ tsp. cayenne pepper
Fresh cilantro, for garnish
Shredded Pepperjack cheese, for garnish

Heat the oil in a large stockpot over medium heat; add the onion and cook 2 minutes. Add the chicken to the stockpot and cook, stirring often, until the chicken is mostly cooked through. Transfer the onions and chicken to a 5-quart Crock Pot; stir in the diced peppers, all of the beans, and the spices. Cover and let cook in the Crock Pot 4-6 hours on high or 8-10 hours on low. To serve, garnish with fresh cilantro leaves and shredded Pepperjack cheese, if desired.