With a fork, prick the eggplant in several places and wrap it in three sheets of aluminum foil. Place directly on the stove burner and cook on medium heat. Using long tongs or an oven mitt to avoid burning yourself, turn the eggplant every 3 or 4 minutes so that it chars evenly all around.
When the eggplant is soft and collapsed, about 15 to 20 minutes, remove it from the heat. Being careful to avoid escaping steam, peel back the foil, slice the eggplant in half lengthwise, and put it in a colander to cool and drain.
While the eggplant roasts, peel and press (or mince) the garlic cloves and squeeze 4 teaspoons of lemon juice. Set aside.
Place the bell pepper directly on a second stove burner and center it to maximize contact with the flame. Adjust the flame to medium-high heat and, using long tongs, turn the pepper every 1 to 2 minutes to char the skin evenly, roasting it for 5 to 10 minutes in all. Place the roasted pepper in a covered bowl or paper bag to cool.
When the pepper is cool enough to handle, use a paring knife or your fingers to peel and discard the skin, then cut it in half and remove the seeds. Scoop the eggplant flesh from its shell.
Finely chop the eggplant and bell pepper. Combine them with the garlic, lemon juice, olive oil, and salt and pepper to taste. Serve at room temperature or chilled.