Preheat oven to 425°F, line baking sheet with parchment
Wash asparagus, pat completely dry
Trim woody ends by bending each spear until it naturally snaps
Arrange asparagus in single layer on baking sheet, don't overlap
Combine olive oil, minced garlic, and lemon zest in small bowl
Let sit 2-3 minutes for flavors to blend
Drizzle garlic oil over asparagus, roll to coat evenly
Sprinkle with salt, black pepper, red pepper flakes if using
Roast 10-15 minutes depending on thickness (thin: 8-10 min, thick: 12-15 min)
Asparagus should be tender when pierced and have caramelized spots
Remove from oven, immediately drizzle fresh lemon juice over hot asparagus
Toss gently to distribute
Sprinkle with Parmesan if using, toss once more
Transfer to serving platter, serve with lemon wedges