Preheat oven to 375 degrees F.
Remove pork from packaging, pat dry with paper towels.
Rub with a little olive oil and season well.
Brown in a pan, just to get color on all sides of the loin, about 10 minutes.
While loin is browning, prepare ingredients in roasting pan or on baking sheet with a deep rim.
Cut sweet potatoes into 1" chunks.
Add garlic cloves, diced shallot and onion, and herbs.
When loin has browned, place into dish over vegetables and place the butter in four pats across the loin.
Add wine to dish.
Cover with lid or wrap with foil.
Roast, covered, for 30 minutes.
Remove lid or foil and continue cooking until the pork reaches an internal temperature of 140 degrees F, another 10-15 minutes.
Let sit on a cooling rack or platter, tented with foil, at least 10 minutes before slicing.
Serve and enjoy!