For me, grilling is often just the first step of a long-term storage process. Much of what we grill ends up in freezer bags, either for long-term storage or as a holding place until we have a big enough batch to fill the canner.
As you try your hand at the recipes on this site, you’ll frequently be referred back to this page for the best way to grill a particular vegetable or fruit for long-term storage. In many cases, the basic process is the same, but a few items have details that will be provided in the relevant blog posts.
Basic Process: Turn, But Don’t Burn
Some vegetables can go whole onto the grill grate and simply need to be watched and turned regularly to ensure even cooking. This includes corn, garlic, asparagus, and small squash.
- Prepare your grill, bringing it up to medium or medium-high heat.
- Prepare your clean vegetables. Corn and whole heads of garlic are best cooked in their husks or skins so that they essentially steam while grilling. Soaking corn husks ensures they don’t catch fire and helps with the steaming. Vegetables like asparagus and small zucchini cook well when tossed lightly in oil, and perhaps ground seasonings, before grilling.
- Place the food on the hot grill and cover, venting as needed to stabilize the heat.
- Slightly undercook any vegetables you plan to freeze; most need only 5–6 minutes. Foods that you plan to eat fresh, particularly those like garlic that caramelize, may want to hang out over the heat for up to 15 minutes. In either case, check and turn the items often to ensure even cooking; because grill temperatures often vary widely, how the vegetable looks and feels is often a better indicator of doneness than a timer.
- Carefully remove the hot vegetables to a bowl or tray. Let them cool at least slightly before handling. If you won’t be processing or eating them straight away, strip the kernels from their corncobs to freeze on trays; place other vegetables on a tray whole. Soft, grilled veggies are easier to chop if you freeze them for a couple of hours first. Once chopped, they can go back into the freezer in bags until you are ready to use or process them.
Follow these same basic steps when applying any of the techniques below.
Skewer or Sheet
Although some foods don’t need to be cut before grilling, they might be too small to lie securely on the grate. Here’s where skewers or a perforated grill tray come in handy. These tools are best for cherry tomatoes, small mushrooms, chilies, and even meals such as shish kababs.
- Prepare your grill and tools. Bamboo skewers like to be soaked before use so that they don’t become brittle and burn. Trays do best with a light oiling.
- Prepare your vegetables, cutting them to the desired size if needed, and threading them onto the skewers or arranging them on the tray. Avoid running the vegetables to the very end or edge; you’ll need room to grasp the skewer or tray.
- Place the food on the hot grill, cover, and vent. Small items often only need to cook a couple of minutes per side.
Cut Above the Rest
Cutting or slicing some vegetables and fruits speeds up the grill time and ensures even cooking. Onions and peppers can simply be cut in half; large eggplant and squashes are better sliced into thick rings.
- Clean and cut the vegetables you plan to cook. Small Japanese eggplant can be halved lengthwise like onions and peppers, but oval Italian ones are best cut into thick rings and drizzled with oil.
- Place the cut side down on the medium-hot grill first, cooking about 5 minutes, until soft and showing grill marks. Then flip each piece over, grilling the opposite side another 3–5 minutes, until lightly charred.
- Remove the hot items to a tray, spreading them out so that they cool quickly through to their centers before peeling or otherwise handling.
Sear to Seal
Tomatoes and tomatillos are among my favorites to grill before canning or freezing. The grilling intensifies their flavor, particularly if you separate the solids and juice, and imparts a smoky tinge that even oven roasting can’t achieve. The trick is to keep the juice from cooking out on the grill and dousing your fire.
- Cut the tomatoes or tomatillos in half at their widest point. Small halves are best grilled on an oiled perforated pan, but large ones can go directly on an oiled grate.
- Place the vegetables cut side down on a hot grill, letting the cut surface sear over for a couple of minutes. Paste tomatoes will likely show grill marks, but large juicy ones are less ideal for grilling and may just soften and sizzle.
- Flip each half and let it cook a further 5 minutes, until soft but still retaining some shape. Overcooked tomatoes may fall apart when you try to lift them from the grate.
- Set a colander in a large bowl so that it is suspended above the bowl’s bottom. Use tongs or a spatula to lift the tomatoes or tomatillos into the colander. Set in a cool space, cover with a towel, and let the vegetables cool and drain completely before using or freezing the solids and juice separately.