Preheat the oven to 400 degrees F.

Toss the tomatoes and zucchini with olive oil, salt and pepper. Arrange in a single layer on a sheet pan with the tomatoes cut-side up. Roast for 25-30 minutes until the tomatoes are wrinkled slightly but still juicy and the zucchini is golden brown at the edges.

While the tomatoes and zucchini are in the oven, cook the orzo until al dente according to package instructions. Drain and transfer the orzo to a large bowl. Stir in the pesto.

Carefully fold the tomatoes, zucchini and chives into the orzo.

Top with grated Parmesan before serving.