Heat olive oil, lemon zest, minced garlic, red pepper flakes, and oregano in a pan over low heat until garlic becomes golden and oil becomes fragrant; remove from heat. (see photo)
Cut ends off of asparagus and discard.
Toss asparagus pieces with olive oil mixture (see photo) and arrange in single layer on a baking sheet.
Season asparagus with salt and pepper and crumble feta cheese on top.
Bake at 400F for 10 mins or until cooked through. (see photo)