Roast or grill asparagus, eggplant, zucchini, squash and pepper. If you're roasting: Preheat oven to 400. Coat vegetables in oil, salt and pepper, and cook for about 40-45 minutes (asparagus will cook in about 25-30). If you're grilling: Coat vegetables in oil, salt and pepper. Grill vegetables over medium high heat, until soft and charred.While vegetables are cooling, toast or grill bread to desired crispness.Smear bread with garlic hummus.Top with eggplant, zucchini, squash, asparagus, red pepper, avocado and any other toppings.Finish by drizzling 1 tsp of balsamic vinegar over sandwich.