Preheat the oven to 400 degrees.
Remove woody ends from the asparagus and rinse well. Pat dry with a paper or tea towel and set aside.
Pour olive oil into a small pan and heat over medium-low heat; you want the oil to be heated, but not too hot or the ingredients will burn. Add in the garlic, lemon zest, oregano, and pepper flakes and cook for two to three minutes, until the garlic just becomes golden. Remove from heat and set aside to cool slightly.
In a large bowl, combine the asparagus, salt, pepper, and infused oil. Mix well to coat the asparagus evenly.
Lay out the asparagus on a baking sheet in an single even layer. Top with crumbled feta cheese and put in the oven for 10-12 minutes.
Remove from oven and squeeze fresh lemon juice over the asparagus.