Salt & pepper the pork loin. Heat oil in a Dutch oven then brown the loin on all sides.
Set the roast fat side up in the Dutch oven and roast, covered, in 350 oven, approximately 20-25 minutes per lb.
While roast cooks, sauté sliced mushrooms, chopped leek or shallot and 3-4 sprigs of thyme in 1 T butter. When golden add crushed garlic and cook another minutes. Remove thyme stems. Stir in cream.
When the roast reaches 145 F, remove from pan and keep warm. Pour the pan juices into the mushroom pan. Deglaze roasting pan with ¼ cup vermouth.
Make a slurry using the vermouth, ¼ cup flour and just enough water to make a smooth, slightly runny paste. Mix the slurry into the mushroom mixture and bring to a boil. Cook until thickened. Adjust flour as needed (amount of juices will vary)
I am not a health professional and nutrition data is calculated programatically. Accuracy may vary with product selection, calculator accuracy, etc. Consult a professional for the best information.