1. Cook the onions, covered, in the oil for 4 minutes in the microwave oven. Drain the tomatoes and reserve the juice. Rub tomatoes through a sieve to remove the seeds.
2. Add tomatoes, bay leaf, thyme, saffron, garlic, and salt to the onions. Cook, uncovered, until thick enough to hold shape softly in a spoon.
3. Peel and cut the eggplant into ½-inch slices. Sprinkle with salt and let set on paper toweling for 20 minutes to pull out any bitter juices. Rinse, pat dry, and brush with oil.
4. The eggplant may be sauteed lightly to brown, if desired, but this is optional. Place one layer of eggplant in a 2-quart rectangular (12-inch by 9-inch) baking dish.
5. Spread with ½ of the tomato sauce, then a row of ½ of the cheese. Add the remaining eggplant, cover with the remaining tomato sauce and then the remaining cheese.
6. Add ¼ to ½ cup of the tomato juice. Cover and cook in the microwave oven until tender. (Should take about 10 to 15 minutes.) Remove cover if too much liquid builds up.
