Heat the vegetable oil in a deep fryer or large pot over medium heat until it reaches 350°F (175°C).

In a medium bowl, whisk together all-purpose flour, garlic powder, paprika, salt, and black pepper.

Pour buttermilk into a separate bowl. This will act as the first dip for your onion rings.

Take each onion ring, dip it into the buttermilk, shake off excess, then dredge in the dry flour mixture.

After coating, return them to the buttermilk for a second dip, then dredge again in panko breadcrumbs.

Carefully place the coated onion rings into the hot oil in small batches and fry for 2-3 minutes until golden brown.

Remove the fried onion rings with a slotted spoon and drain excess oil on a paper towel-lined plate.