How to Roast Garlic
Preheat the oven to 400 degrees. Slice the top off your head of garlic. Place each head of garlic on a small piece of foil and drizzle a teaspoon of olive oil over the top. Wrap loosely in the foil. Place on a tray (to make removing it from the oven simple) or if your foil wrapped clove is large enough, just set it on the rack in the oven.
Roast until the head of garlic is soft and golden brown. I usually leave mine in the oven from 45-60 minutes. It is often soft by the 30 minute mark, but I like mine a deep golden brown. (I've never overcooked it, even when I've forgotten and left it in the oven for 90 minutes.) I test mine simply by squeezing the foil wrapped roasting garlic with a pair of kitchen tongs.
Carefully remove from the oven and let cool. Unwrap and use your fingers to squeeze the roasted garlic out of the clove. You can also use the tines of a fork to pull the cloves out separately. If you won't be using it right away, roasted garlic can be stored in the refrigerator for several days. Store the garlic in an airtight container, unless you'd like everything else in the refrigerator to have a rich garlic aroma as well!