Heat a small frying pan over medium heat and lightly coat with cooking oil spray.
Crumble the feta cheese into the pan, spreading it evenly and covering the outer edges.
Let the feta sizzle for 1–2 minutes until it begins to melt and turn golden.
Gently crack the egg into the center of the pan.
Season with dried oregano and red pepper flakes, then cook the egg to your liking.
Warm the tortilla or toast the bread. Smash the avocado on top and finish with a squeeze of lemon juice.
Once the feta forms a crisp crust and the egg is cooked, carefully lift it out with a spatula and place it on the tortilla.
Garnish with pickled onions and a drizzle of chili oil. Serve immediately and enjoy your Crispy Feta Fried Eggs.