Cook the orzo in a large pot of salted boiling water until al dente, then reserve about 1/2 cup of the pasta water before draining. Drain the pasta and set aside.

In the same pot, heat the olive oil and sauté the garlic until fragrant, about 1 minute. Add the diced zucchini and tomato, season with salt and pepper, and cook until tender, about 3 to 4 minutes.

Add the cooked orzo back into the pot and stir to combine all ingredients. If the mixture seems dry, add some of the reserved pasta water as needed.

Stir in the grated Parmesan or Pecorino cheese until melted and combined. Serve immediately.