Wash and dry all produce. 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 wedges. Toss zucchini and tomato with 1 TBSP olive oil and half the Italian seasoning. Season with salt and pepper.
Place veggies on a baking sheet. Roast in oven until zucchini is golden brown and tomato softens, 20-25 minutes. Meanwhile, chop mozzarella into ½-inch-thick cubes. Halve lemon.
Once water boils, add half the orzo (we sent more). Cook until al dente, 9-11 minutes. Drain and return to pot. Squeeze in juice of half the lemon. Season to taste with salt and pepper.
Cut three quarters of the way through each chicken breast (parallel to cutting board). Open up like a book, cover with plastic wrap, and flatten with a large pan. Season on all sides with salt, pepper, and remaining Italian seasoning. Heat a drizzle of olive oil in the pan over medium-high heat. Add chicken and cook until cooked through, 3-4 minutes per side. Remove from pan.
With 5 minutes left on veggies, remove baking sheet from oven. Heat broiler to high or increase oven to 500 degrees. Sprinkle veggies with panko, mozzarella cheese, and Parmesan cheese. Broil until cheese is melted and panko is golden brown, 3-5 minutes.
Plate orzo and top with cheesy roasted veggies and chicken breast. Pour over any juices from plate and a squeeze of remaining lemon.