Dice or slice the eggplant. There aren't really rules here apart from try to cut them into uniform size because different size of eggplant pieces will roast differently.
Sprinkle salt and optional spices and herbs on top then let it sit for about 20 minutes.
Place the pieces onto a parchment paper lined baking sheet. Mind the pieces don't overlap or at least not too much. We can simply place them onto a wire rack but they keep falling off. Placing them directly onto a baking sheet is also an option but they tend to stick and burn so be careful with that too. Some like to brush or spray them with cooking oil but if we count calories, no amount of oil is welcome.
Place the eggplant onto the middle rack of a 390°F / 200°C preheated oven until golden brown spots start to appear on the eggplant, about 20 - 30 minutes.
Move the pieces around, flip the slices then put it back until both sides are similarly browned, about 10 - 20 minutes more.