1. 1. Cook the pasta: Bring a large pot of salted water to a rolling boil. Add the penne pasta and cook according to package directions until al dente. Before draining, reserve about 1/2 cup of the starchy pasta water. Drain the pasta and set aside.

2. 2. Prepare the chicken: While the pasta cooks, pat the cubed chicken breasts dry with paper towels. In a medium bowl, toss the chicken with olive oil, Italian seasoning, garlic powder, salt, and pepper until evenly coated.

3. 3. Saute the chicken: Heat a large skillet or Dutch oven over medium-high heat. Add the seasoned chicken and cook for 5-7 minutes, stirring occasionally, until it’s golden brown and cooked through. Remove the chicken from the skillet and set it aside.

4. 4. Cook the vegetables: In the same skillet, add the broccoli florets and bell peppers. Saute for 3-5 minutes until they start to become tender-crisp. Add the halved cherry tomatoes and frozen peas, cooking for another 2-3 minutes until the tomatoes soften slightly and the peas are heated through.

5. 5. Build the sauce: Pour the chicken broth and fresh lemon juice into the skillet with the vegetables. Bring it to a simmer, scraping up any browned bits from the bottom of the pan. Stir in the butter until it melts and the sauce is slightly thickened.

6. 6. Combine everything: Return the cooked chicken and drained pasta to the skillet with the vegetables and sauce. Toss everything together gently to ensure the pasta and chicken are well coated. If the sauce seems too thick, add a splash or two of the reserved pasta water to reach your desired consistency.

7. 7. Finish and serve: Stir in the grated Parmesan cheese until it melts into the sauce. Taste and adjust seasonings if needed. Garnish with fresh chopped parsley and serve immediately with extra Parmesan cheese on the side.