01 -
Combine the mayonnaise, sour cream, horseradish, ketchup, paprika, garlic powder, and cayenne pepper in a small bowl. Mix thoroughly and refrigerate until ready to serve.
02 -
Whisk egg and milk in a bowl wide and deep enough to fully submerge the onion.
03 -
In a separate wide bowl, mix flour, paprika, cumin, dried oregano, thyme, salt, cayenne pepper, black pepper, and garlic powder until well combined.
04 -
Cut a small flat area on the non-root end of each onion. Remove any dried or damaged outer peels. Place the onion flat side down on a cutting board with the root side up. Using a sharp knife, cut the onion into quarters, stopping about 1.5 cm from the root to keep the onion connected. Further divide each quarter into three or four equal sections. Turn the onion root side down and gently fan out the sections.
05 -
Carefully coat each onion with the flour mixture, gently spreading and separating the petals to ensure complete coverage. Dunk the floured onion into the egg mixture, then return it to the flour mixture, using your hands to thoroughly coat all surfaces.
06 -
Heat vegetable oil in a heavy, deep pan to 190°C (375°F). Use enough oil to completely cover the onion. Fry each onion root side up for 7-10 minutes or until golden brown. Transfer to paper towels to drain excess oil.
07 -
Serve immediately with the prepared dipping sauce.