Heat oven to 350°F.
Combine butter with onion, marjoram and sage.
Heat a metal roasting pan on the stove over medium high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Halve potatoes and place cut-side down in the hot pan. Cook until golden brown, flip and turn off the heat. Add the wine or stock to the potatoes and season with salt and pepper.
Rub pork with flavored butter and aggressively season with salt and pepper. Arrange the pork over the potatoes and dot with remaining butter. Roast about 1 hour and 30 minutes until the internal temperature reaches 145°F on a meat thermometer.