Melt Becel® Buttery Taste margarine* in small nonstick skillet over medium heat and cook shallot and garlic, stirring occasionally, until shallot is tender, about 4 minutes.Remove from heat, then stir in orange juice, marmalade, mustard, rosemary and black pepper; set aside.
Arrange pork tenderloin in baking pan lined with aluminum foil. Pour 1/2 of the marmalade mixture over pork.
Roast 10 minutes. Baste pork with remaining marmalade mixture. Roast an additional 10 minutes or until internal temperature reaches 155°F to 160°F (68°C to 71°C). Remove from oven; tent loosely with aluminum foil, then let stand at least 5 minutes before slicing.