I've tried a few different beer-battered onion rings through the years, but these are by far THE best (hence the name!)
1 1/2 C all purpose flour
1 egg, separated
About 3/4 C beer
2 T melted butter
1 t paprika
salt to taste
2 medium/large onions sliced into rings (I used 1 large white onion and 1/2 of a large sweet onion)
Vegetable/canola oil for frying (anything is fine, just not olive oil)
Sift 1 cup flour into a large bowl. In another large bowl, melt butter and then whisk in egg yolk, beer and salt.. Set aside 1/2 cup of flour in a large ziploc bag for dipping the onion rings. Slowly stir the egg yolk mixture into the remaining flour and mix well. Allow the mixture to stand 30 minutes. The mix should have a pancake batter consistency, add more beer if necessary.
Heat about 1-2" of oil in a large pan.
In a small bowl, stiffly beat the egg white. Gently combine the egg white with the batter.
Put all onion rings into the large ziploc baggie with flour and shake to coat. Dip each ring into batter.
Deep fry the battered rings, several at a time, until golden brown. Drain on paper towels or brown paper bags and serve.If you are prepping in advance or in a larger batch, keep them warm on a baking sheet in the oven at lowest temperature.
And, if you get to the end and you have some onion pieces that aren't really rings or you're just plain tired of standing at the stove dropping onions into oil, just mix all your pieces into whatever batter you have left and dump the whole mess into the oil for a giant fritter that's just as delicious as all the other rings!