Make pasta: In a 3-quart saucepan, heat 8 cups of water to boiling. Add the orzo and vegetable blend, bring to a boil and simmer 8-10 minutes.
Drain and rinse with cold water, shake well to drain completely. In a separate bowl, combine the seasoning mix, 1 tablespoon oil and 2 tablespoons water. Add orzo. Toss to coat with dressing.
Refrigerate for one hour before adding remaining ingredients.
Combine diced onion, sliced tomatoes and grapes with orzo. Refrigerate one hour. Before serving garnish with fresh grated Parmesan cheese.