Preheat oven to 400 degrees F. Cut off top 1/2 inch of garlic bulb to expose ends of individual cloves. Leaving bulb whole, remove any loose, papery outer layers. Place bulb, cut end up, in a muffin or custard cup or on a double thickness of foil. Drizzle bulb with oil. Cover with foil or bring foil up around bulb and fold edges together to loosely enclose. Roast 35 to 40 minutes or until garlic feels soft when squeezed; cool.
Squeeze garlic cloves and juices into a medium saucepan. Add remaining ingredients. Bring to boiling over medium-high heat, stirring occasionally; reduce heat. Simmer, uncovered, 30 minutes or until thickened, stirring occasionally.