It's made by consistently heating whole heads of garlic over the course of several weeks, which results in something similar to roasted garlic, but even more earthy and caramelized in taste. (golubkakitchen.com)
Throw in a few whole heads of garlic... and I am in. (floandgrace.com)
Cut 2 whole heads of garlic in half crosswise. (bonappetit.com)