Start by peeling and slicing your onions into thin strands. Aim for about 1/8-inch thick; this thickness helps them fry evenly and get crispy. I often use a mandoline slicer for this task, but you can use a sharp knife.

Place the sliced onions in a mixing bowl, then cover them with buttermilk. Let them soak for at least 30 minutes. This step is essential, as it softens the onions and enhances flavor. If you're short on time, even a 15-minute soak can make a difference.

In a shallow dish, combine the flour, onion powder, garlic powder, smoked paprika, black pepper, salt, and cayenne pepper. Mix it thoroughly to ensure all the spices are evenly distributed.

In a deep, heavy pan or a deep fryer, pour in about an inch of oil and heat it to 375°F (190°C). To test if it’s hot enough, drop in a small piece of onion—if it sizzles immediately, you’re ready to fry.

Working in batches, remove a handful of onions from the buttermilk and allow the excess to drip off. Dredge them in the flour mixture, ensuring they are fully coated. Shake off any excess flour as you go.

Carefully add the coated onions to the hot oil, frying in small batches to avoid overcrowding. Fry them until they are golden brown, stirring occasionally to promote even frying—this usually takes about 2–4 minutes.

Using a slotted spoon, remove the crispy onion strings from the oil and place them on a paper towel-lined plate to drain excess oil. Sprinkle with a little salt while they’re hot for added flavor.