Preheat the broiler with an oven rack about 6 inches below the heating element. Line a rimmed baking sheet with foil.

Prick the whole eggplants several times with a fork and arrange them on the baking sheet. Broil, turning with tongs every 8 to 10 minutes, until the skin is charred and blistered all over and the eggplants have completely collapsed and feel very soft, 25 to 35 minutes depending on their size and your broiler.

Let the eggplants cool until you can handle them, about 10 minutes. Slit them open, scoop the flesh into a colander, and discard the skins and stems. Let the flesh drain for 10 minutes.

Meanwhile, heat the oil in a skillet over medium heat. Add the onion and sauté until translucent, about 5 minutes. Add the garlic and continue to sauté, stirring often, until the onion is golden brown, 5 to 7 minutes more.

Combine the drained eggplant, the onion and garlic mixture, the tahini, lemon juice and cumin in a food processor. Pulse until the mixture is a slightly chunky purée. Season with salt and pepper, then taste and add more tahini or lemon juice if you like.

Transfer to a shallow serving bowl and swirl the top with the back of a spoon. Drizzle with olive oil and sprinkle with paprika and parsley, if using. Serve at room temperature with pita or raw vegetables.