Some Grilled Vegetables Need Another Prep Step Before Grilling

Grilling vegetables is undoubtedly one of the most delectable methods of cooking them, as they effortlessly absorb a layer of deep, smoky flavor. And getting those perfectly charred grill marks on top makes any vegetable simply irresistible. Most veggies can be grilled — you can even even grill your own pickles. But with some, it's much easy to achieve the desired tenderness without burning the outside. Others, like potatoes, require a bit of extra care before hitting the grill. It mainly comes down to texture.

For vegetables with a firm exterior and a softer interior, such as zucchini, onion, bell peppers, and mushrooms, they can be directly placed on the grill grates after oiling and seasoning. On the other hand, vegetables with a firm exterior and interior or which are particularly fibrous, like potatoes, carrots, beets, artichokes, cauliflower, or fennel, need to be pre-cooked before grilling. Partially cooking them in advance cooking allows their tightly-bound structure to begin to break down, ensuring that the outside doesn't burn while the inside thoroughly cooks through. For others, like eggplant, soaking them for 30 minutes in a saltwater brine before drying and grilling will give the best results.

The pre-cooking methods for these types of veggies is simple: microwaving, boiling, or steaming. I'm partial to par-boiling firmer types of vegetables over the other cooking methods, as I can do a large batch at once. Boiling also allows you to salt the water, which seasons the veggies while trapping in moisture. This means that when the're grilled, they won't become dry inside. But if you're in a hurry to get one of these firmer veggies on the grill and aren't cooking very many at once, a microwave can still get the job done.

For any pre-cooking method, ensure the vegetables are cleaned, trimmed, or peeled before boiling or microwaving. With some, such as beets, it's easier to leave them whole during pre-cooking and slice them before grilling. You're looking to cook them until they're about halfway done, so the timing will depend on the type; it might be four or five minutes for carrots, or 10 minutes for new potatoes. To determine if your vegetables are just-tender, check you can pierce a fork or skewer into the center of their flesh. 

The thickness of the slices or chunks is also vital for successful grilled vegetables — if they're too thick, it will slow down the heat from the grill penetrating through the flesh, and we're back to square one. As a general guideline, aim for somewhere around ¼ to ½ inch thick for most types. Try to make slices of roughly equal sizes so they cook evenly. Obviously if you're wanting to make a whole BBQ cauliflower that outshines everything else on your grill, it will take longer — though you can still par-boil it first to reduce the time. If you want to get ahead, you can even pre-cook your vegetables in advance, and refrigerate them until you're ready to grill.

Coat your veggies in oil or fat, and thoroughly season them before grilling. Alternatively, to amp-up the flavor even further, you can quickly marinate the vegetables after pre-cooking in a dry seasoning, a sauce, or even use vanilla extract for grilling. Either way, the pre-cooking technique makes for a great grilled vegetable side dish, or even the main course.