Combine the ingredients together in a small jar with a lid. Shake to combine. Set aside until ready to serve.

Slice the bell pepper in half. Remove the seeds and core. Cut each piece in half.

Peel the onion and slice into four rounds. Insert tooth picks into the sides of each round to hold the onion slices together.

Cut the eggplant in half lengthwise. Using a small paring knife, cut a crisscross pattern in the flesh taking care not to cut through the skin.

Slice the zucchini and squash in half lengthwise.

Thread the mushrooms and small tomatoes on skewers. If using larger tomatoes, cut in half.

Clean the corn removing the husks and silk.

Brush all vegetables with olive oil and season with salt and pepper.

Grill the vegetables until well charred and cooked through. Grill the eggplant, pepper and squash flesh side down first then turn once to grill the other side. To achieve good grill marks, try not to move the vegetables around until charred.

Remove the vegetables to a baking tray as they are done. Some may take longer than others to cook through. Once cooled enough to handle, scoop the flesh out of the eggplant using a large spoon. Discard the skin. Remove the skin from the peppers and tomatoes if desired. Chop the larger vegetables into bite sized pieces. Cut the corn from the cob and cut the onion rings in half. Toss the vegetables together and serve warm or at room temperature drizzled with the vinaigrette as desired.