2large onionspeeled and cut in half (leave the ends on, it'll help the onions stay together. You can remove them after they've been grilled and chilled)
6white zucchiniscut in half
3celery stalksleaves removed
1yellow bell pepperstem and seeds removed and cut in half
Sprinkle your vegetables with salt and pepper and place them on the grill, cut side down when applicable.
Lower heat to medium, close the lid and cook your vegetables until they become nice and soft and get some nice grill marks on them, about 10 to 15 minutes (the eggplant might take a little bit longer)
Allow your vegetables to cool down a bit then transfer then to a large container with a fitting lid.
Place in the refrigerator to cool overnight or until completely chilled.
Transfer the cooled vegetables to your food processor (don't forget to remove the ends off the onions if you left them on) add the rest of the ingredients and process until smooth.
Serve immediately or allow to sit in the refrigerator for a couple of hours to allow flavors to develop.
Garnish with unripened goat cheese and raw pumpkin seeds, if desired.