How to grill vegetables. The key to charred perfection is actually quite simple.

Aug. 2, 2022
Roasted vegetables. Photo courtesy of Bill St. John.
Learn how to grill vegetables with ease. It’s relatively simple to make sweet, charred perfect veggies. Photo courtesy of Bill St. John.

Smoke is a flavor. So is char. However, when we’re out grilling our food, I believe that we attend to these two, by and large, less as flavors and more as either an aroma or an optic. For example, “Check out the great char on that steak,” he said.

Another enormously important and intricate flavor that we often conflate with a simple char is the so-called caramelization of sugars and amino acids on grilled foods called the Maillard reaction, named after its discoverer, the French scientist Louis Camille Maillard. Nearly anything brown or dark brown on any cooked food (baked, fried, sautéed, grilled, seared, “browned,” roasted, deep-fried, even dried) is a result of the Maillard reaction. It produces complex flavors, aromas and background tastes, especially umami.

I say “so-called” caramelization because to caramelize anything is, in essence, to darken merely its sugars, not its amino acids. But the Maillard reaction also darkens these latter.

But again, we generally highly prize the “little black bits” on grilled vegetables, fish or meats as a visual esthetic, not a flavor. But to me, they are flavor primarily and most importantly.

To that end, I wanted to devise a recipe for an array of grilled vegetables that would accentuate these three flavors of smoke, char and “caramelization,” unbusied by other flavors such as those in many a marinade (for instance, herbs, vinegar, juice or wine), from a dry rub (the flavor possibilities here are nearly innumerable) or a wet nap (again, too many possible flavors to count).

In the recipe here, the prepped vegetables hit the grill seasoned with good olive oil, salt and pepper only. The other flavors that they gain, they gain from the fire of the grill alone.

It is key to have the highest heat possible; the higher the heat, the stronger those flavors. So, build well the fire of thy grill.

Whichever sort of grill that you use, make one zone that is nearly too hot to approach, 600 degrees or so: a large pile of white-hot coals mounded on one side of the kettle, or one region of the grill turned up way high. (I learned when younger that a grill’s fire reached its proper cooking temperature when I could hold my hand just above the grill grate and barely finish saying the word “Massachusetts.” Because of the extra heat in this recipe, you shouldn’t be able to whip out “Boston.”)

Then slope the coals (or turn on another set of the burners) so that there is a second zone around 350-400 degrees. And finally, secure a third zone under which there is no flame at all.

Salt and pepper grilled vegetables with grilled Olathe Sweet Corn ‘Confetti’

Serves 4-6, depending on portion size or use (for example, in a sandwich or atop steamed rice). The list of vegetables here is simply suggestive. You may choose as you desire; most any vegetable is grillable.


1 each medium-to-large zucchini, yellow summer squash and longish eggplant

1 each red and orange (or yellow) bell pepper

1 long hot chile pepper (such as Hatch or Pueblo)

3 caps of portobello mushroom, each about 4 inches in diameter

1/2 small head radicchio

1 large bok choy

3 thick “Chinese large onions” or 6 thick scallions

1 lemon

1 ear Olathe Sweet corn

1 1/2 cups good quality, flavorful extra virgin olive oil

2 tablespoons freshly ground black pepper

3 tablespoons medium-grained sea or kosher salt


Prep the vegetables. Wash them all (except the mushroom caps), if necessary. Trim then slice the squashes and eggplant lengthwise into strips just under 1/2-inch thick. Trim then section the bell peppers at their natural folds and seed them. Trim then seed the hot chile.

Trim off any stub from the bottom of the mushroom caps and brush or wipe off any soil or debris. Section the radicchio half into 8 wedges, keeping each wedge as one “book” of leaves by retaining in it some of the core. Trim the onions or scallions of any roots or thickened green leaves.

Slice the lemon along its “equator” into 4 pieces. Husk the ear of corn and rub off all the silk. Set and separate the prepped vegetables onto 2-3 large baking sheets or trays lined with parchment paper.

Pour the olive oil into a large bowl. Now dunk, bathe or otherwise generously coat each vegetable piece (including the entire ear of corn) and replace it on its baking sheet. Add more oil if called for.

Grievously pepper and mercilessly salt each vegetable piece on both sides and replace it on its sheet. Have the grill fire ready.

Cook the vegetables. Using long tongs, grill the vegetables in groups, about 3-4 minutes each side (replacing the grill top to smoke out any flareups, if necessary) utilizing the hottest zone first for 2-3 minutes, then the next hotter zone for another 1-2 minutes. (Some vegetables, such as the mushroom caps, may take longer or finish cooking in the “cool zone.”) Grill the corn cob off to one side of the hottest zone, turning it with the tongs as kernels darken and brown.

As the vegetables finish grilling, place them back on their trays (or on freshly prepared trays), going on to the next group and so on.

When finished, set the corn aside until the cob is cool enough to handle. Remove the kernels from the corn by slicing down along the cob with a sharp-edged knife (such as a filet knife) and set aside.

Serve the vegetables as desired, with the corn kernels sprinkled atop as “confetti.”

Reach Bill St John at [email protected]

About the author

For more than 40 years, Bill St. John’s specialties have been as varied as they are cultured. He writes and teaches about restaurants, wine, food & wine, the history of the cuisines of several countries (France, Italy, Spain, Belgium, and the USA), about religion and its nexus with food, culture, history, or philosophy, and on books, travel, food writing, op-ed, and language.

Bill has lent (and lends) his subject matter expertise to such outlets as The Rocky Mountain News, The Denver Post, The Chicago Tribune, 5280 Magazine, and for various entities such as food markets, wine shops, schools & hospitals, and, for its brief life, Microsoft’s In 2001 he was nominated for a James Beard Award in Journalism for his 12 years of writing for Wine & Spirits Magazine.

Bill's experience also includes teaching at Regis University and the University of Chicago and in classrooms of his own devising; working as on-air talent with Denver's KCNC-TV, where he scripted and presented a travel & lifestyle program called "Wine at 45"; a one-week stint as a Trappist monk; and offering his shoulder as a headrest for Julia Child for 20 minutes.

Bill has also visited 54 countries, 42 of the United States, and all 10 Canadian provinces.