Cook the pasta according to package directions until al dente. Drain and set aside.

While the pasta cooks, heat the olive oil in a large pan or skillet over medium-high heat.

Add the chicken pieces to the hot pan and cook, stirring occasionally, until browned and cooked through, about 5-7 minutes.

If using, add the chopped onion and cook until softened, about 3-4 minutes.

If using, add the minced garlic and cook for 30 seconds until fragrant.

Add the chopped vegetables to the pan and cook for 5-7 minutes, or until tender-crisp.

Season the chicken and vegetables with salt and pepper.

If using, stir in the tomato passata or chopped tomatoes and simmer for 2-3 minutes.

Add the cooked pasta to the pan with the chicken and vegetables. Stir gently to combine everything.

Serve hot, garnished with fresh herbs if desired.