Cook the Orzo: Bring a large pot of salted water to a rolling boil. Add the orzo pasta and cook for about 8–10 minutes until al dente. Drain and rinse under cold water to cool.

Prep the Vegetables: Dice the red and orange bell peppers, red onion, cucumber, and tomatoes into bite-sized pieces. Add corn, chopped basil, and sliced green onions, then fold in the cooled orzo.

Make the Dressing: In a small bowl, whisk together olive oil, juice and zest of lemon, Italian seasoning, Dijon mustard, and minced garlic. Add salt and pepper to taste.

Combine Everything: Pour the dressing over the orzo and vegetable mixture. Toss gently to coat the ingredients evenly.

Serve or Chill: Transfer to a serving platter and garnish with Parmesan cheese or refrigerate for at least 30 minutes before serving.