1Dice the eggplant into 1/3 to 1/4 inch cubes. Toss diced eggplant into a colander with at least a couple of teaspoons of salt and let stand over bowl or sink. Allow the eggplant to drain for about an hour.
2Preheat the oven to 425 deg. F and drain the eggplant well. Rinse it, and drain it again. Squeeze as much liquid out as possible, and oil a rimmed baking sheet generously with olive oil. Toss the eggplant cubes onto the sheet and mix them well with the oil. Add pepper and roast the eggplant until it is creamy and tender.
3While allowing the eggplant to cool, cut the cucumber and the tomato into about 1/4 inch dice. Thinly slice the onions and toss with a small pinch of salt. Pour vinegar over the mixed veggies to combine. Allow time to marinade in the fridge.
4Once the eggplant has cooled, and the salad had time to marinade, combine the eggplant, the oil in which it was roasted and the feta with the salad. Stir well, and enjoy with crusty bread.