Add chicken, cook chicken until it becomes white on the outside. Add fresh tomatoes, tomato paste, water, chili powder, cumin, paprika, oregano, and salt. Stir to combine well, then allow to come to simmer. Cook for about 2 minutes.
Add black beans, celery, and bell pepper. Stir to combine well. If it's too thick, add a little more water.
Keep cooking the chili until it becomes your desired consistency.