Sear chicken in a skillet or pan over medium heat until browned all over (or in your 6-quart instant pot on 'sear/sauté' setting). Transfer chicken to your slow cooker or instant pot bowl. Add the diced onion, red peppers (capsicum), corn, creamed corn, potatoes, chicken broth and garlic powder. Stir and cover with lid; cook on slow cooker high setting for 3-4 hours or low setting 6-8 hours. For Instant Pot, set to Pressure Cook on Soup setting for 30 minutes.Once potatoes are fork tender and chicken is falling apart, stir the cream (or milk) and milk/cornstarch mixture through the chowder. Mix well; cover and allow to thicken on 'keep warm' setting until thickened.Optional: Using a stick blender, blend the bottom of the chowder only for a couple of seconds to puree some of the potatoes to make the chowder thicker. Alternatively, use a potato masher.Stir in salt and pepper to taste; add in the cheese; top with the bacon; garnish with fresh chives and serve.