Char the eggplants directly on the stove, in the flame. Flip them every 2 minutes until they're completely charred. You can line up the stove with aluminum foil for an easier clean up.
Cover the eggplants in a bowl for a few minutes, this will steam the and make the peeling process a lot easier. Peel the eggplants, then let them sit in a sieve, over a bowl, until most of their bitter juices come out. Let them cool off completely before mixing the with the rest of the ingredients.
Mix the eggplants (you can chop them first for a smoother dip), v mayo, garlic, onion, salt, pepper, and lemon juice in a bowl until combined. Add more mayo to taste, start with ½ cup and keep adding as you please.
Serve everything with olive oil on top, sumac and other spices.