In a small bowl, mix the Balsamic Marinade ingredients together.
Divide all the veggies between two large ziplock bags and add in, except the beef tomatoes, cherry tomatoes and the onions. Pour the marinade into both bags, leaving a few tablespoons behind. Toss the bags to distribute the marinade. Allow the veggies to marinate for at least 30 minutes but up to a day.
Heat and prepare your grill while the veggies are marinating. When ready, add the veggies to the grill at high heat, either directly to the grill for larger veggies, or to a grill sheet or foil for all the other veggies.
Add the red onion slices, beef tomatoes and cherry tomatoes onto the grill too, and brush with the remaining balsamic glaze. Brush all the other veggies with any remaining glaze too.
Grill the veggies until tender. The timing will vary slightly; about 5-6 minutes for the cherry tomatoes mushrooms, eggplants and zucchini and about 10-15 minutes for the bell peppers, red onions and beef tomatoes. the straight grill for larger veggies.
Remove from the grill into an aluminium foil container, and lightly season with salt and pepper over the top. Serve and enjoy!
Notes
Refrigerator: You can keep the veggies wrapped in foil or in an airtight container for 4 to 5 days. I don’t recommend freezing this recipe.
To reheat: Place the veggies in a microwave-safe dish and microwave until warmed through or reheat them in a 350ºF oven or toaster oven. You can also eat them cold as an addition to salads.