Preheat the oven to 425 degrees F.
Toss the mushrooms and asparagus with the oil on a baking sheet and roast, stirring once, until tender and brown in spots, about 15 minutes.
Meanwhile, grind the chiles in a spice grinder until coarsely ground into flakes. Mix the chiles with the salt and lemon zest in a small bowl.
Transfer the asparagus and mushrooms to a serving bowl and sprinkle with 1/2 teaspoon of the chile-lemon salt.