In a small saucepan, combine balsamic vinegar, honey, and Dijon mustard. Heat over medium until simmering, then reduce to low and cook for about 10 minutes until it thickens. Remove from heat and cool.

Bring salted water to a boil, add orzo pasta and cook according to package instructions (around 8-10 minutes). Drain and rinse under cold water. Toss with olive oil.

Halve grape tomatoes, cube mozzarella, and tear basil. In a mixing bowl, combine these with cooled orzo.

Drizzle olive oil over the mixture, season with salt and pepper, and toss gently.

Portion into bowls, drizzle with balsamic syrup, and garnish with basil before serving.