Wash and dry all produce. Adjust rack to upper position and preheat oven to 425 degrees. Bring a large pot of salted water to a boil. Slice zucchini into ¼-inch-thick rounds. Cut tomato into ½-inch-thick wedges. Toss zucchini and tomato with 1 TBSP olive oil and half the Italian seasoning on a baking sheet. Season with salt and pepper.

Roast veggies in oven until just shy of tender, about 10 minutes. Once water is boiling, add half the orzo from package to pot (use the rest as you like). Cook, stirring occasionally, until al dente, 9-11 minutes. Drain, then return to pot.

With your hand on top of one chicken breast, cut ¾ of the way through middle, parallel to cutting board, stopping before you slice through completely. Repeat with other chicken breast. Open each up and season all over with salt, pepper, and remaining Italian seasoning.