These meals are not from the J.O. 30 Minute Meals cook book but they are from his website http://www.jamieoliver.com/ They are fantastic and I highly recommend them even if you aren't used to eating either beetroot or aubergine/eggplant.
Disclaimer: I have never been a big fan of aubergine or eggplant as it is called where I grew up. I have always found it to be foamy when raw and gooey when cooked and particularly lacking in flavor or bitter. But as my favorite vegetarian pointed out to me once-"you probably don't like it because you have never had a good eggplant before". I think that was true, but really it was only one of the problems. The second problem was that I had never cooked it in the right way before.
So tip #1 Picking Your Eggplant
If your eggplant sounds hallow it will turn out to be the foamy kind inside. Pick them heavy, shiny, on the smaller side, and give it the thumb press test. Press your thumb into the side and if indents and springs back it is ripe :) I don't know if it is true but I read that you should look for an eggplant that has the smallest dimple in the bottom, rather than those with larger dimples.
Tip #2 Cooking the eggplant
Most things I have read tell you to sweat your eggplant before cooking to avoid the bitter taste, but in this recipe I didn't find that necessary. I simply grilled the eggplant dry without oil and they dried up in cooking and never got soggy.
I do have a tip for making this salad as well though: make sure your watercress is really fresh. It starts to loose its nice flavor and gets old more bitter.To do this look for dark green leaves and stems that are firm. Avoid any that are turning yellow or feel slightly slimy. The other tips for the salad have to do with the beats. One is to wear gloves when thinly slicing your beet root to avoid red fingers for the next three days :) The other is to peel them. He says just to wash and not peel but if you are even slightly worried about the flavor of the beets I would peel them. I always peel mine and I never get that dirty bitter taste.
FYI: I didn't have any white wine or herb vinegar for the bruschetta so I substituted red wine vinegar instead and it was wonderful.