Preheat oven to 425° F. Prepare a large baking sheet by spraying with nonstick cooking spray or lining with parchment paper. In a small bowl, mix together the olive oil, lemon juice, garlic, rosemary, parsley, lemon zest, salt and pepper.
Place potatoes, mushrooms and chicken breasts on the baking sheet in an even layer. Pour on the lemon mixture and toss chicken, potatoes and mushrooms until evenly coated. Bake for 15 minutes.
While the chicken, mushrooms and potatoes are baking, trim the ends of the asparagus. Toss asparagus with a little bit of olive oil and season to taste with salt and pepper. When the chicken, potatoes and mushrooms come out at the 15-minute mark, add the asparagus to the pan. Put everything back in the oven to continue cooking for 8-10 minutes.