adapted by http://theresalwaysthyme.blogspot.com/
2 heads of garlic
1 tablespoon olive oil
salt
Preheat oven to 350 degrees F.
Slice about a third off the top, pointed end of the garlic bulbs. Remove any loose paper from whole heads of garlic as you can, don't break apart the cloves.
Place it on a large piece of aluminum foil and drizzle it with the olive oil.
Bring the foil over the sides of the garlic and twist to seal it, not too tight. Place it in a small baking dish and roast in the oven for about 45 minutes. Bake until the garlic is soft and easily pierced with a thin-bladed knife. Squeeze the roasted garlic from the clove. Wait until it cools a bit, then squeeze the cloves out. Or use a fork!
To make garlic compound butter: leave a stick of unsalted butter on the counter while the garlic roasts, so it will come to room temperature. When the garlic has roasted and cooled a bit, squeeze the cloves into a bowl, and take the room temperature butter and mash it all together. Take the mixture and plop it on a piece of parchment, wax paper or plastic wrap, then roll it up into a log. Twist the ends to tighten it up. Throw it in the freezer and slice off a piece whenever you need it. Use 3 to 6 cloves of roasted garlic per stick of butter, depending how strong you like the flavor. I used 5 very small cloves to one stick of butter.