Braising is a long, slow cooking process that tenderizes meats and develops flavors. First the food in browned in hot fat, then it is cooked tightly covered in a small amount of liquid.
The purple eggplant commonly found in U.S. markets doesn't resemble and egg, but a small white-skinned Asian variety does. Japanese eggplant is also purple, but is more slender and slightly sweeter than the larger kind. Choose eggplants that feel heavy for their size.
While some purists turn up their noses at "old-fashioned" sauces thickened with cornstarch, the fact remains that cornstarch adds body without fat. For best results, dissolve the cornstarch in a small amount of liquid, then pour the dissolved mixture into the sauce to be thickened.