Cook orecchiette pasta according to package directions until al dente. Reserve 1 cup pasta water, then drain and set aside.
While pasta cooks, heat 2 tablespoons olive oil in a large skillet over medium-high heat. Add zucchini, yellow squash, and bell pepper. Cook for 5-6 minutes, stirring occasionally, until vegetables are tender and lightly browned.
Add garlic and cook for 1 minute until fragrant, then add cherry tomatoes and Italian seasoning. Cook for 3-4 minutes until tomatoes begin to break down.
Stir in the shredded rotisserie chicken and cook for 2 minutes until heated through.
Add the cooked pasta to the skillet along with 1/2 cup reserved pasta water. Toss everything together, adding more pasta water if needed to create a light sauce.
Remove from heat and stir in remaining tablespoon of olive oil, lemon juice, salt, and pepper. Top with Parmesan cheese and fresh basil before serving.