Cut the eggplants in half, lengthwise, and scoop out the flesh, leaving 1/2 inch on the shell.
Chop the scooped-out flesh into 1/2 inch cubes and set in a colander. Sprinkle the eggplant cubes and the inside of the eggplant shells with salt. Let stand for 30 minutes, then rinse and pat dry.
Bring a large pot of salted water to boil. Drop the eggplant shells in the water and simmer for 7 minutes. Shells should be barely tender when poked with a fork. Drain and pat dry.
Heat the olive oil in a large skillet over medium heat. Sauté the onions for 5 minutes.
Add the chopped eggplant, tomatoes, walnuts, cinnamon, oregano and 1/4 cup filtered water. Cook for 8 minutes, until softened and browned.
Preheat oven to broil. Place eggplant shells on a greased baking sheet. Broil for 5 minutes. Reduce oven heat to 375 degrees F.
Fill each eggplant shell with the cooked veggies and sprinkle feta on top. Bake for 35 minutes, or until browned on top.
Nutritional Analysis: One serving equals: 153 calories, 4.7g fat, 86mg sodium, 25g carbohydrate, 11g fiber, and 6g protein.