For the white BBQ sauce, combine all its ingredients in a bowl and whisk to combine. Thin with a splash of plant milk or water if you want a thinner consistency. Set aside.
slice the onions into ½ - inch thick rings and separate them. (Optional: Soak in ice water for 20 minutes for extra crispness, then pat dry.)
Next, place the panko breadcrumbs in a shallow bowl, along with the garlic powder, onion powder, smoked paprika, 1 teaspoon of salt and 1 teaspoon pepper, whisking to combine.
In a separate shallow bowl, whisk together the flour and remaining 1 teaspoon salt and fresh cracked black pepper, garlic powder, onion powder, and smoked paprika.
Gradually whisk in cold water until smooth. The batter should be thick enough to coat but still run slightly.
Dip each onion ring into the wet batter, gently tapping off excess batter.
Press and roll the battered ring into the panko until fully coated.
Repeat the process until all the onion rings are coated in the breadcrumbs.
Meanwhile, heat the oil in a large sauté pan over medium heat.
Once the oil is hot (you’ll know when you sprinkle a few breadcrumbs into the oil and sizzles immediately), fry the onion rings in batches until golden and crispy, 2 to 3 minutes per side.
Drain on a wire rack or paper towel-lined plate and sprinkle immediate with little salt while hot, optional. Sprinkle with fresh minced parsley and serve with a side of white BBQ sauce. Enjoy!