Step 1: Prepare the Onions

Peel the onions and slice them into ½-inch thick rounds. Separate the rounds into individual rings, discarding the very small center rings (save these for another use or fry them as “bonus bites”). Pat the rings dry with paper towels – removing excess moisture is important for coating adhesion. Set aside on a clean kitchen towel or paper towels.

Step 2: Set Up Your Dredging Station

Place three shallow bowls or pie plates in a row on your workspace. In the first bowl, add ½ cup of flour. In the second bowl, whisk together buttermilk, eggs, and water until smooth. In the third bowl, combine the remaining 1 cup flour, cornstarch, all the seasonings (garlic powder, onion powder, paprika, salt, pepper, cayenne if using), and baking powder. Whisk thoroughly to distribute the spices evenly.

Step 3: Heat the Oil

Pour oil into your large, heavy-bottomed pot or Dutch oven to a depth of 3-4 inches (the pot should be no more than halfway full for safety). Heat over medium-high heat until a deep-fry thermometer reads 375°F. This will take about 10-15 minutes. While the oil heats, you can start coating your onion rings.

Step 4: Double-Coat the Onion Rings

Working with 4-5 onion rings at a time, first dredge them in the plain flour (bowl #1), shaking off excess. Next, dip into the buttermilk mixture (bowl #2), letting excess drip off. Finally, coat thoroughly in the seasoned flour-cornstarch mixture (bowl #3), pressing gently to ensure it adheres well. Place coated rings on a wire rack or clean plate. Repeat until all rings are coated. This double-coating creates that extra-crispy texture!

Step 5: Fry in Batches

Once oil reaches 375°F, carefully add 4-6 onion rings to the hot oil using tongs or a slotted spoon (don’t overcrowd the pot). Fry for 2-3 minutes, flip with a slotted spoon or spider strainer, and fry for another 2-3 minutes until deep golden brown on both sides. The coating should look crispy and the onions should be tender inside.

Step 6: Drain and Season

Use a slotted spoon to carefully remove the onion rings from the oil, letting excess oil drip off. Transfer to a wire rack set over a baking sheet (or paper towels). While still hot, sprinkle with a pinch of salt. The salt sticks best when the rings are fresh from the oil.

Step 7: Maintain Oil Temperature & Repeat

Between batches, let the oil return to 375°F before adding more rings. This is crucial – if the oil is too cool, the onion rings will absorb oil and become greasy instead of crispy. Continue frying all the rings in batches.

Step 8: Serve Immediately

Onion rings are best served hot and fresh from the fryer! Pile them on a serving platter with your favorite dipping sauces and enjoy immediately while they’re at peak crispiness.