Herbed Eggplant Dip

1 medium onion chopped
1/3 cup olive oil
a 1-pound eggplant, cut into 1/4-inch dice
1 teaspoon salt
2 plum tomatoes, seeded and diced
3 tablespoons fresh lemon juice
1/4 cup fresh basil leaves, washed well, spun dry, and minced
2 tablespoons minced fresh parsley leaves
Accompaniment: garlic flavored Melba toasts or assorted crudites

In a large heavy skillet cook onion in oil over moderate heat, stirring, until softened. Add eggplant and salt and cook, stirring, until eggplant begins to brown, about 10 minutes. Cover skillet and cook eggplant, stirring occasionally, 5 minutes, or until tender. Remove skillet from heat and cool eggplant. Stir in remaining ingredients and salt and pepper to taste. Serve eggplant dip with toasts or crudites.