Heat your vegetable oil in a deep fryer or a sturdy pot over medium-high heat until it reaches 350°F (175°C).

In a mixing bowl, combine the all-purpose flour, garlic powder, paprika, salt, and black pepper. Whisk thoroughly until uniform.

Pour buttermilk into a separate shallow bowl for dipping the onion rings.

Dip each onion ring into the buttermilk, allowing excess to drip off, then coat evenly in the flour mixture.

Return the coated onion ring to the buttermilk briefly, then dredge it in panko breadcrumbs.

Fry the onion rings in small batches for about 2-3 minutes until golden brown.

Remove fried onion rings with a slotted spoon and place them on a plate lined with paper towels to drain excess oil.

Serve warm with your favorite dipping sauces.