Always place food horizontally on the cooking grates — or the opposite direction of the cooking grates, never parallel. When you place the food in the same direction as the grates, you run the risk of having it slip through the grates. Even more important, you won’t get good grill marks on whatever you are grilling. The best marks are short and go across the food.
Grill over a medium, direct heat and turn the vegetables once halfway through the cooking time; each vegetable will vary in the amount of time it needs. Really dense vegetables such as potatoes will need to be finished with indirect heat or the outside will burn by the time the inside is tender.
When you remove the grilled vegetables, place them in a single layer on a sheet pan lined with a wire rack so they can cool completely before they are stored in the refrigerator. Make the sandwiches or serve the vegetables room temperature with a drizzle of fruity olive oil and a pinch of crunchy salt.
GRILLED VEGGIE SANDWICH WITH ROASTED GARLIC MAYONNAISE
Because the vegetables are good hot or cold, they can be grilled ahead and refrigerated. Assemble the sandwiches just before serving.
Start to finish: 11/2 hour (30 minutes active)
2 red bell peppers
2 yellow bell peppers
1/2 cup balsamic vinegar
1/4 cup olive oil, plus more for the rolls
1 teaspoon dried rosemary
Kosher salt and ground black pepper
6 large portobello mushrooms, stems removed
1 medium zucchini, cut into 6 long strips
6 kaiser or onion rolls (or 12 thick slices of sourdough bread)
Head of roasted garlic (see recipe below)
1/2 cup mayonnaise
1 bunch fresh basil, leaves only
1/2 pound chunk Parmigiano-Reggiano cheese, thinly sliced with a vegetable peeler
1/2 pound thinly sliced prosciutto (optional)
Prepare and heat a gas or charcoal grill for high heat, direct grilling.
Place the red and yellow bell peppers on the grill grate and cook, turning frequently, until the skin is charred all over, about 5 minutes per side. Use tongs to remove the peppers from the grill and place them in a large bowl. Cover the bowl tightly with plastic wrap. Set aside for 30 minutes. After 30 minutes, the skins should slip easily off the peppers. Slice them open, remove the seeds, then cut into large strips.