For eggplant, I like
baba ghanoush. In the summer, grilling the eggplant with smoke gives it an especially nice flavor.
Ratatouille is also good - in summer, you can grill all the vegetables and then dress it as a warm salad/side dish.
I also make matchsticks of zucchini to match peppers and onions when I cook or grill vegetables for fajitas.