In a large mixing bowl, combine the olive oil, minced garlic, lemon zest, lemon juice, sea salt, black pepper, and red pepper flakes. Whisk until well blended.
Add the trimmed asparagus to the bowl and toss gently, coating each spear in the lemon-garlic mixture.
Spread the asparagus in a single layer on a baking sheet lined with parchment paper for easy cleanup.
Roast in the preheated oven for 15-20 minutes, or until the asparagus is tender and lightly browned, tossing halfway through for even cooking.
Once done, remove from the oven and sprinkle with grated Parmesan cheese if desired.
Serve hot, garnished with fresh lemon slices for an added touch of brightness.
Notes
Add red pepper flakes for extra heat and Parmesan cheese for richness.