Cooks traditionally throw away the first boiling water specifically to cut the eggplant's natural bitterness before it's stewed.
Small bitter African eggplants called impwa are boiled — often with the first water discarded to tame the bitterness — then simmered with tomato and onion into a soft, tangy relish eaten over nshima. Around Livingstone it's a common side ordered alongside grilled bream or chicken.