Saute carrots, celery, shallots, and peppers in 2 tablespoons of olive oil for about 3 minutes.
Add broth and all other ingredients except for citrus and parsley.
Turn up heat to boil and turn down to low-med to simmer.
Simmer for 45-50 minutes.
Finish by squeezing in citrus juice and zest and parsley (if using).
