Wash and pat the 4 eggplants dry and trim the stem ends.
Place the whole eggplants directly on the flame of your stove. Using tongs, roast them, turning when the side on the flame has blackened; continue turning and roasting until the entire skin is evenly blackened and blistered.
Immediately transfer the roasted eggplants to a bowl and cover with a lid. Let them rest, covered, until they have cooled to room temperature.
Once cool, cut off any remaining stem ends (if needed), peel away and discard the charred skins, and discard any tough bits.
Using two forks, shred and mash the eggplant flesh to your desired consistency. Set the shredded eggplant aside.
Heat 6 tablespoons olive oil over low heat in a skillet. Add the 1 large minced red onion and cook, stirring, until the onion is translucent.
Add the 1 diced bell pepper and the 4 crushed garlic cloves to the skillet and cook, stirring, for 1 minute.
Add the shredded eggplant to the skillet and stir to combine. Season with 1 1/4 teaspoons salt (or to taste) and 1/2 teaspoon black pepper (or to taste).
Stir in 1 cup tomato sauce, cover the skillet, and simmer over low heat for 7 minutes.
Taste and adjust salt if necessary. Remove from the heat, sprinkle with 1 tablespoon minced parsley, and serve.