Preheat oven to 375°

Cut top off garlic head to expose cloves. Place on foil, and top with chopped rosemary. Drizzle in oil. Wrap loosely in foil and bake 50-60 minutes, or until soft and golden

Place potatoes and apples in pot with enough water to cover. Add salt, cover pot and bring to boil. Reduce heat to medium, simmer 10 minutes, or until potatoes are soft

Drain, and reserve 1 cup cooking water. Transfer potatoes and apples to serving bowl

Squeeze roasted garlic gloves into potatoes and apples. Add vinegar

Mash. Add water if neccessary to adjust texture for creaminess