Whisk up the dressing (olive oil, mustard, salt, pepper, garlic, and Italian seasoning) and set aside.
If using wooden skewers, soak them for 15-20 minutes to prevent burning.
Preheat your grill over medium heat (about 350-450 degrees).
Alternating ingredients, skewer all of the ingredients, for example, sausage, onion, pepper, mushroom, zucchini and then repeat.
Brush dressing mixture on all of the kabobs.
Grill 4-5 minutes on each side or until vegetables are tender and sausage is warmed and golden.
Alternatively, you could toss all of the vegetables and sausage in the dressing and bake in the oven on a baking sheet at 400 degrees for about 20 minutes.