Preheat oven to 450 degrees.
Line a 15 1/2″ by 10 1/2″ jelly-roll pan with nonstick foil. Place eggplant halves, skin-sides up, in foil-lined pan.
Wrap garlic in foil and place in pan with eggplants. Roast vegetables 45 to 50 minutes or until eggplants are very tender and skin is shriveled and browned.
Unwrap garlic. Cool eggplants and garlic until easy to handle.
Scoop eggplants’ flesh into food processor .Squeeze out garlic pulp from each clove and add to processor with tahini, lemon juice, and 3/4 teaspoon salt; pulse to coarsely chop
Spoon dip into serving bowl; stir in cilantro.
Cover and refrigerate at least 2 hours.