Preheat the barbecue to high or put a grill pan on a high heat to get nice and hot. Slice the eggplant about ½ inch (1 cm) thick, slice the fennel bulb at an angle about 1/8 inch (3 mm) thick, then slice the zucchini lengthways in about the same thickness as the fennel. Snap the woody ends off of the asparagus. Leave the sweet peppers and patty pans, if using, whole.
Pile everything onto a large baking sheet ready to cook. In batches, add the veggies to your barbecue or hot grill pan to cook for about 5 to 10 minutes, or until charred, soft and delicious. Remember that each vegetable will cook in a different amount of time so keep checking and turning everything and as soon as it is looking good, transfer it to a large bowl (keeping the cooked peppers and patty pans to one side) and get the next lot of veggies on.
Carefully remove the black skin on the peppers, open them up and scrape away the seeds. Don’t worry about getting all of the skin off but do the best you can. This is a messy job but totally worth it! Tear the peppers up into strands and add to the bowl. Halve the patty pans and add those too, along with the extra virgin olive oil, red wine vinegar and a good pinch of salt and pepper. Gently toss it all together and have a taste to check the seasoning, then fold through the basil leaves, reserved fennel tops and garlic.