Start by sauteing onion, peppers and olive oil in a large skillet on the stove. Cook for about 5 minutes until tender. Add in 1 tbsp flour and cook for another 2 minutes. Remove from heat.
Meanwhile, add chicken breasts to the crock pot and season. Add in onions and peppers.
Pour in chicken broth and add in cream cheese. Cover and cook on high for 3 hours.
After 3 hours remove chicken and chop in to bite size pieces. Add in spaghetti, stir to prevent sticking. Cook about 30 minutes and taste. Stir pasta one more time. Top with cheddar cheese. Cover and cook remaining 30 minutes.