Crush the fennel seeds to a powder mix with salt. Score the pork and rub the fennel and salt mixture over the meat. Set aside.
Trim the greenery and stalks off fennel and discard. Dice the bulb. Mix with carrots, celery, garlic, and onions.
Place all the veggies in roaster. Set roast on top of veggies. Set the thyme and rosemary sprigs in roaster.
Pour wine and chicken broth over the whole thing. Cover with foil and roast in 300 degree oven for 3 to 4 hours.
Remove roast and set aside to rest. Remove the thyme and rosemary. Dump the veggies and juice into a saucepan and simmer to reduce. Use a immersion blender or food processor and puree the sauce. Serve over roast.