Preheat your oven to 375°F (190°C). Bring a large pot of salted water to a boil and cook 8 oz of penne pasta until just al dente, about 1-2 minutes less than package instructions. Drain and set aside. Meanwhile, toss 1 lb of trimmed asparagus pieces in 2 tablespoons olive oil, salt, and pepper. Spread them on a baking sheet and roast in the oven for 10 minutes until tender-crisp and slightly caramelized.
In a medium skillet over medium heat, warm 2 tablespoons olive oil. Add 2 cloves minced garlic and sauté until fragrant, about 1 minute. Pour in 1 cup heavy cream and 1 cup chicken or vegetable broth, stirring to combine. Add 1 teaspoon lemon zest, 1/4 cup lemon juice, 1/2 teaspoon dried oregano, 1/2 teaspoon dried thyme, and season with salt and pepper to taste. Let the sauce simmer gently for 3-4 minutes until it slightly thickens. Stir in half of the grated Parmesan cheese to melt into the sauce.
In your baking dish, mix the cooked penne pasta, roasted asparagus, and optional cooked shredded chicken or turkey if using. Pour the lemon cream sauce evenly over the top and gently toss to coat. Sprinkle the remaining Parmesan cheese over the surface.
Bake uncovered for 20 minutes, or until the cheese on top is golden and the sauce is bubbling around the edges.
Remove from the oven and sprinkle with 1/4 cup chopped fresh parsley for a vibrant herbal finish. Let the pasta bake rest for 5 minutes before serving to allow the sauce to settle.