In a medium Dutch oven over medium heat, cook pork in batches in oil until no longer pink; remove and keep warm.
In the same pan, saute onion until crisp-tender. Add garlic; cook 1 minute longer.
Add the broth, vegetables, vinegar, sugar, tarragon and salt; bring to a boil.
Reduce heat; cover and simmer for 25-30 minutes or until vegetables are tender.
Combine flour and milk until smooth; gradually stir into vegetable mixture.
Bring to a boil; cook and stir for 2 minutes or until thickened.
Add pork and heat through.
Reduce heat; stir in sour cream just before serving (do not boil).
If desired, top with parsley and cracked pepper.
