Cook the penne pasta according to package instructions until al dente. Drain and set aside, reserving 1/2 cup of pasta water.

In a large skillet, heat the olive oil over medium-high heat. Add the chicken pieces, season with garlic powder, salt, and pepper, and cook until browned and cooked through, about 5-7 minutes. Remove the chicken from the skillet and set aside.

In the same skillet, add the asparagus and cook for 3-4 minutes until tender-crisp. Add the cherry tomatoes and cook for an additional 2 minutes.

Return the cooked chicken to the skillet. Add the cooked pasta, lemon zest, lemon juice, and reserved pasta water. Toss everything together until well combined and heated through.

Stir in the grated Parmesan cheese until melted and creamy. Adjust seasoning with salt and pepper if needed.

Serve immediately, garnished with fresh parsley.