Preheat the oven to 350°F. Trim the top ¼ inch off the top of each head of garlic.
Place the garlic cut-side up on a piece of foil large enough to wrap the garlic, drizzle with olive oil, and sprinkle with salt. Nestle the garlic in the foil in a small baking dish and fold the foil over the garlic.
Roast for 40 to 60 minutes or until the cloves are deep golden brown and tender.
Serve the roasted garlic with a spoon or knife to remove the cloves from the head to spread on crostini, or in other recipe ssuch as mashed potatoes.