Place tenderloin in shallow baking pan. Roast at 350°F for 30 minutes or until juicy and slightly pink in center.
Heat oil in medium saucepan. Cook onion and garlic over low heat for 5 minutes. Combine onion and garlic with remaining ingredients in food processor; process until almost smooth. Heat mixture in saucepan thoroughly over low temperature, stirring frequently. Serve over tenderloin slices.