Cut the top of the onion; place it cut-side down, and, using a sharp knife, make ½-inch cuts in a circular motion to create “petals.”
Flip the onion over and, using your hands, begin coaxing apart its layers.
In a large bowl, combine flour, cayenne, paprika, oregano, salt, garlic powder and black pepper.
Place the onion cut-side down in the bowl, cover with a plate, and shake to coat onion and each “petal.” Shake off any excess flour.
Meanwhile, in a separate medium bowl, mix eggs with milk. Dip onion in egg wash cut-side down; shake off excess egg wash and return onion to flour mixture to coat a second time. Shake off any excess flour.
In a deep-fryer or a heavy Dutch oven, heat oil to 375 F, adding enough oil so the entire onion will be able to float.
In the deep-fryer or Dutch oven, add the onion cut-side down in the oil for 2-3 minutes, then carefully flip the onion and allow it to fry for an additional 2-3 minutes or until the batter is golden brown.
Move it to a plate covered in paper towels to drain off excess oil and season with a little salt.
Serve immediately with L&B Mojito Lime Aioli or L&B Chipotle Aioli for dipping.