Season the chicken with salt and pepper. Heat a large stockpot to medium to medium-high heat. Spray with olive oil and add chicken. Cook a few minutes until mostly cooked through. Remove from pan and cover.
Spray pot with oil and add onion, celery, carrots, garlic, thyme and oregano. Sauté 2-3 minutes until softened. Return chicken to the pot. Reserve a couple tablespoons of broth and add the rest of the broth and green beans to the pot. Turn heat to medium-low.
Meanwhile, add beans and reserved broth to a blender. Blend until smooth. Add beans to the stockpot.