At the yoga centre where I cook we roast zucchini in the oven.
Slice in half, drizzle with olive oil, season with salt and pepper, bake until just cooked, slightly brown if you like them that way, or very brown and shrivelled if you like extra taste (and less of the final product).
When they are cooked (or a little brown), crumble feta cheese on top, back in the oven (15 minutes maybe - depends on oven, I can't remember!) until the feta is browned.
A classic for us in Crete - ingredients always fresh and available.
For the eggplant: sliced in rounds, drizzled with oil, salt and pepper and roasted can be yummy just on its own.
It would need to go in ahead of the zucchini. You can also turn the eggplant over when it's starting to soften, and put a slice of tomato on top. Slice of mozzarella on top of that is another option - back into the oven until tomato is softened mozarella softened, or crispy if you prefer.
When I worked there last year we joked last year we had a bilingual kitchen - cooking with aubergine and eggplant, courgettes and zucchini, oreganum, or-e-ga-no and o-reg-a-no and tom- ah-toes and tom-ay-toes.
For me, growing up with my Mum's recipe books from England, Australia and the US, means I'm fluent in metric/imperial and centigrade/farenheit. This probably is part of the reason I found Maths so easy at school. (or "Math" for US readers.
My culinary multilingualism (multicuisinism? multimeasuringism?) runs out when it comes to"Gas Mark 5", and I'd be a little stumped by an Aga, although I have seen it on TV.