The trick to these tasty rings is soaking them in the beer and some vinegar first. This softens them up so the only thing left to do is make their battered outside golden!
Cut the onions into 1/4 inch slices. Separate the rings and place them in a large bowl with the beer, water, salt and vinegar. Let it sit at room temperature for at least 2 hours, up to 4.
After the onions have soaked, lay on paper towels to dry.
Mix together all the ingredients for the batter and, using a wire whisk, blend well.
Dredge the rings in flour first, then dip into the batter. Deep fry in 350ᵒ oil until they are golden brown.
Remove from the oil and place on paper towels. Keep repeating the process until all the rings are done. Salt lightly with sea salt that has been mixed with just a pinch of malt vinegar powder (the powder is optional).
Let rest in a warm oven (about 300ᵒ) in one layer for about 5 to 10 minutes then serve hot!