Long, slow roasting transforms garlic from sharp to mellow and changes its texture from firm to lusciously, spreadably soft. Roasted garlic isn't just for spreading on bread. You can mash the tender cloves into potatoes, a vinaigrette, or a shrimp and pasta toss.
With a sharp knife, cut off the top 1/2-inch from each garlic bulb to expose the ends of individual cloves. leaving garlic bulbs whole, remove any loose, papery outer layers.
Fold four 18x9-inch pieces of heavy foil in half to make 9-inch squares. Place each garlic bulb, cut side up,in center or a foil square. Drizzle the bulbs with olive oil and sprinkle with salt, basil, oregano, and pepper. Bring up opposite edges of foil and seal with a double fold. Fold remaining edges together completely to enclose garlic, leaving space for steam to build.
For charcoal grill, arrange medium-hot coals around a drip pan. Test for medium heat above the pan. Place foil packets with garlic on grill rack over drip pan. Cover and grill foil packets for 35 to 40 minutes or until garlic bulbs feel soft when packets are squeezed, turning packets occasionally. (For a gas grill, preheat grill. Reduce heat to medium. Adjust for indirect cooking. Grill as above.)
To serve, unwrap garlic and transfer to serving plates. Squeeze garlic pulp from each clove; spread onto toasted bread. Makes 4 appetizer servings.