Rub pork with olive oil, and sprinkle with salt. Stir together garlic and next 4 ingredients; press onto pork. Place pork on a rack in a lightly greased broiler pan; cover bone tips with aluminum foil to prevent burning.
Bake at 350° for 1 hour and 15 minutes or until a meat thermometer inserted into thickest portion registers 160°. Transfer pork to a serving tray. Pour pan drippings into a skillet.
Add butter to drippings; cook over medium heat until butter melts. Whisk in flour until smooth. Cook, whisking constantly, until caramel colored. Gradually whisk in broth and next 3 ingredients; cook over medium heat, whisking constantly, 2 to 3 minutes or until mixture is thickened and bubbly. Serve with pork. Garnish, if desired.
Note: Ask your butcher to French-cut the racks for a nice presentation. A rack of pork is bone-in, fresh pork loin.