Marinate in lots of extra-virgin olive oil, fresh chopped garlic,
chopped fresh sage leaves, and cracked black peppercorns. Before
grilling, drain off most of oil and reserve garlic, sage leaves
and cracked pepper.
In a skillet, saute reserves garlic and sage lightly along with
small amount of finely chopped onion. Deglaze pan with ruby port,
add a splash of chicken stock and balsamic vinegar. Reduce to
about 2/3 cup. Grill tenderloin. When done, slice and pour sauce