Preheat oven to 475 degrees. Gently toss asparagus with olive oil and place on a large baking sheet, spacing the stalks as far apart as possible. Bake 5–6 minutes, or longer depending on thickness and desired tenderness of your asparagus. Turn the stalks or give the pan a shake about halfway through roasting.
Meanwhile, whisk together olive oil, lemon juice, lemon zest, rosemary and mustard until it becomes emulsified. Set aside.
Remove asparagus from oven and transfer to a serving platter. Spoon dressing over the asparagus then sprinkle with Parmesan cheese, kosher salt and pepper. Serve immediately while nice and warm.
One Last Thing
Roasting veggies like asparagus is the best way to get the most flavor out of them!