Cook the penne according to package directions. Reserve ½ cup pasta water before draining.
During the last 3 minutes of cooking, add the asparagus to the pasta pot. Drain both together.
Meanwhile, heat the olive oil in a large skillet over medium heat. Add the garlic and cook for about 30 seconds until fragrant.
Stir in the broth, lemon juice, lemon zest, and light cream cheese. Whisk until smooth.
Add the cooked pasta and asparagus to the skillet. Toss to coat. Add a little reserved pasta water if needed to create a silky sauce.
Remove from heat and stir in the Parmesan and parsley.
Season with salt and black pepper.