Preheat oven to 400 degrees F. Cut the eggplant into 1-inch cubes and put in a large bowl. Add the olive oil, garlic, green onions, ground cumin, paprika powder, balsamic vinegar, salt and pepper. Toss until coated.
Spread the eggplant on a large baking sheet, lined with parchment. Roast in the oven until very tender and slightly browned, about 45 minutes (stir every 15 minutes and check to make sure it isn't burning.) Remove from the oven and cool slightly.
Return the eggplant to the bowl and toss with soy sauce and lemon juice. Add the walnut and parsley. Transfer to a serving dish and sprinkle feta cheese on top.