Place asparagus, portabello mushrooms and zucchini on a roasting pan, drizzle with olive oil.
Roast in a 375 degree oven for 30-40 minutes or until lightly browned.
Meanwhile, add lime juice, vinegar, dijon mustard, honey and sea salt into a bowl. Slowly add olive oil and whisk together until emulsified. Stir in chopped shallots and fresh ground pepper.
Arrange chopped romaine onto a large serving dish.
When vegetables are perfectly roasted, remove them from the oven and add to a large bowl with avocado, corn, beans and scallions.
Pour dressing on top and mix until all vegetables are well coated, place on top of chopped romaine lettuce.